diff --git a/include/boost/multi_index/detail/any_container_view.hpp b/include/boost/multi_index/detail/any_container_view.hpp
new file mode 100644
index 0000000..8bcd278
--- /dev/null
+++ b/include/boost/multi_index/detail/any_container_view.hpp
@@ -0,0 +1,83 @@
+/* Copyright 2003-2021 Joaquin M Lopez Munoz.
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ * See http://www.boost.org/libs/multi_index for library home page.
+ */
+
+#ifndef BOOST_MULTI_INDEX_DETAIL_ANY_CONTAINER_VIEW_HPP
+#define BOOST_MULTI_INDEX_DETAIL_ANY_CONTAINER_VIEW_HPP
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
+
+namespace boost{
+
+namespace multi_index{
+
+namespace detail{
+
+/* TODO: WRITE */
+
+template<typename ConstIterator>
+struct any_container_view_vtable
+{
+  ConstIterator (*begin)(const void*);
+  ConstIterator (*end)(const void*);
+};
+
+template<typename Container>
+typename Container::const_iterator any_container_view_begin(const void* pc)
+{
+  return static_cast<const Container*>(pc)->begin();
+}
+
+template<typename Container>
+typename Container::const_iterator any_container_view_end(const void* pc)
+{
+  return static_cast<const Container*>(pc)->end();
+}
+
+template<typename Container>
+any_container_view_vtable<typename Container::const_iterator>*
+any_container_view_vtable_for()
+{
+  static any_container_view_vtable<typename Container::const_iterator> vt=
+  {
+    &any_container_view_begin<Container>,
+    &any_container_view_end<Container>
+  };
+
+  return &vt;
+};
+
+template<typename ConstIterator>
+class any_container_view
+{
+public:
+  template<typename Container>
+  any_container_view(const Container& c):
+    pc(&c),
+    pvt(any_container_view_vtable_for<Container>())
+    {}
+
+  const void*   container()const{return pc;}
+  ConstIterator begin()const{return pvt->begin(pc);}
+  ConstIterator end()const{return pvt->end(pc);}
+
+private:
+  const void*                               pc;
+  any_container_view_vtable<ConstIterator>* pvt;
+};
+
+} /* namespace multi_index::detail */
+
+} /* namespace multi_index */
+
+} /* namespace boost */
+
+#endif
diff --git a/include/boost/multi_index/detail/index_base.hpp b/include/boost/multi_index/detail/index_base.hpp
index 973c2c9..3ded1c2 100644
--- a/include/boost/multi_index/detail/index_base.hpp
+++ b/include/boost/multi_index/detail/index_base.hpp
@@ -179,7 +179,7 @@ protected:
 
   template<typename MultiIndexContainer>
   final_node_type* insert_(
-    const value_type& v,final_node_type*& x,MultiIndexContainer* p)
+    const value_type&,final_node_type*& x,MultiIndexContainer* p)
   {
     p->final_extract_for_transfer_(x);
     return x;
diff --git a/include/boost/multi_index/detail/ord_index_impl.hpp b/include/boost/multi_index/detail/ord_index_impl.hpp
index 9afe20f..149f681 100644
--- a/include/boost/multi_index/detail/ord_index_impl.hpp
+++ b/include/boost/multi_index/detail/ord_index_impl.hpp
@@ -128,13 +128,6 @@ template<
 >
 class ordered_index_impl:
   BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS SuperMeta::type
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  ,public safe_mode::safe_container<
-    ordered_index_impl<
-      KeyFromValue,Compare,SuperMeta,TagList,Category,AugmentPolicy> >
-#endif
-
 { 
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
@@ -178,8 +171,7 @@ public:
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   typedef safe_mode::safe_iterator<
-    bidir_node_iterator<index_node_type>,
-    ordered_index_impl>                              iterator;
+    bidir_node_iterator<index_node_type> >           iterator;
 #else
   typedef bidir_node_iterator<index_node_type>       iterator;
 #endif
@@ -229,8 +221,7 @@ protected:
 
 protected:
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef safe_mode::safe_container<
-    ordered_index_impl>                              safe_super;
+  typedef safe_mode::safe_container<iterator>        safe_container;
 #endif
 
   typedef typename call_traits<
@@ -731,6 +722,11 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     super(args_list.get_tail(),al),
     key(tuples::get<0>(args_list.get_head())),
     comp_(tuples::get<1>(args_list.get_head()))
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
     empty_initialize();
   }
@@ -739,13 +735,13 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     const ordered_index_impl<
       KeyFromValue,Compare,SuperMeta,TagList,Category,AugmentPolicy>& x):
     super(x),
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super(),
-#endif
-
     key(x.key),
     comp_(x.comp_)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
     /* Copy ctor just takes the key and compare objects from x. The rest is
      * done in a subsequent call to copy_().
@@ -757,13 +753,13 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
        KeyFromValue,Compare,SuperMeta,TagList,Category,AugmentPolicy>& x,
      do_not_copy_elements_tag):
     super(x,do_not_copy_elements_tag()),
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super(),
-#endif
-
     key(x.key),
     comp_(x.comp_)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
     empty_initialize();
   }
@@ -775,9 +771,9 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   iterator       make_iterator(index_node_type* node)
-    {return iterator(node,this);}
+    {return iterator(node,&safe);}
   const_iterator make_iterator(index_node_type* node)const
-    {return const_iterator(node,const_cast<ordered_index_impl*>(this));}
+    {return const_iterator(node,const_cast<safe_container*>(&safe));}
 #else
   iterator       make_iterator(index_node_type* node){return iterator(node);}
   const_iterator make_iterator(index_node_type* node)const
@@ -904,7 +900,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     empty_initialize();
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::detach_dereferenceable_iterators();
+    safe.detach_dereferenceable_iterators();
 #endif
   }
 
@@ -918,7 +914,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     adl_swap(comp_,x.comp_);
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_(x,swap_allocators);
@@ -929,7 +925,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
       KeyFromValue,Compare,SuperMeta,TagList,Category,AugmentPolicy>& x)
   {
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_elements_(x);
@@ -1531,6 +1527,10 @@ protected: /* for the benefit of AugmentPolicy::augmented_interface */
   key_from_value key;
   key_compare    comp_;
 
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+  safe_container safe;
+#endif
+
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
 #pragma parse_mfunc_templ reset
diff --git a/include/boost/multi_index/detail/safe_mode.hpp b/include/boost/multi_index/detail/safe_mode.hpp
index ce81fa3..e64cebb 100644
--- a/include/boost/multi_index/detail/safe_mode.hpp
+++ b/include/boost/multi_index/detail/safe_mode.hpp
@@ -18,9 +18,9 @@
 
 /* Safe mode machinery, in the spirit of Cay Hortmann's "Safe STL"
  * (http://www.horstmann.com/safestl.html).
- * In this mode, containers of type Container are derived from
- * safe_container<Container>, and their corresponding iterators
- * are wrapped with safe_iterator. These classes provide
+ * In this mode, containers have to redefine their iterators as
+ * safe_iterator<base_iterator> and keep a tracking object member of
+ * type safe_container<safe_iterator<base_iterator> >. These classes provide
  * an internal record of which iterators are at a given moment associated
  * to a given container, and properly mark the iterators as invalid
  * when the container gets destroyed.
@@ -83,6 +83,11 @@
     safe_mode::check_is_owner(it,cont),                                      \
     safe_mode::not_owner);
 
+#define BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,cont)               \
+  BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
+    safe_mode::check_belongs_in_some_index(it,cont),                         \
+    safe_mode::not_owner);
+
 #define BOOST_MULTI_INDEX_CHECK_SAME_OWNER(it0,it1)                          \
   BOOST_MULTI_INDEX_SAFE_MODE_ASSERT(                                        \
     safe_mode::check_same_owner(it0,it1),                                    \
@@ -117,6 +122,7 @@
 #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
 #include <algorithm>
 #include <boost/multi_index/detail/access_specifier.hpp>
+#include <boost/multi_index/detail/any_container_view.hpp>
 #include <boost/multi_index/detail/iter_adaptor.hpp>
 #include <boost/multi_index/safe_mode_errors.hpp>
 #include <boost/noncopyable.hpp>
@@ -165,18 +171,29 @@ inline bool check_decrementable_iterator(const Iterator& it)
   return (it.valid()&&it!=it.owner()->begin())||it.unchecked();
 }
 
-template<typename Iterator>
+template<typename Iterator,typename Container>
 inline bool check_is_owner(
-  const Iterator& it,const typename Iterator::container_type& cont)
+  const Iterator& it,const Container& cont)
 {
-  return (it.valid()&&it.owner()==&cont)||it.unchecked();
+  return (it.valid()&&
+            it.owner()->container()==cont.end().owner()->container())
+         ||it.unchecked();
 }
 
+template<typename Iterator,typename MultiIndexContainer>
+inline bool check_belongs_in_some_index(
+  const Iterator& it,const MultiIndexContainer& cont)
+{
+  return (it.valid()&&it.owner()->end().get_node()==cont.end().get_node())
+         ||it.unchecked();
+} 
+
 template<typename Iterator>
 inline bool check_same_owner(const Iterator& it0,const Iterator& it1)
 {
-  return (it0.valid()&&it1.valid()&&it0.owner()==it1.owner())||
-         it0.unchecked()||it1.unchecked();
+  return (it0.valid()&&it1.valid()&&
+            it0.owner()->container()==it1.owner()->container())
+         ||it0.unchecked()||it1.unchecked();
 }
 
 template<typename Iterator>
@@ -487,36 +504,36 @@ void safe_iterator_base::detach()
 namespace safe_mode{
 
 /* In order to enable safe mode on a container:
- *   - The container must derive from safe_container<container_type>,
+ *   - The container must keep a member of type safe_container<iterator>,
  *   - iterators must be generated via safe_iterator, which adapts a
- *     preexistent unsafe iterator class.
+ *     preexistent unsafe iterator class. safe_iterators are passed the
+ *     address of the previous safe_container member at construction time.
  */
  
-template<typename Container>
+template<typename Iterator>
 class safe_container;
 
-template<typename Iterator,typename Container>
+template<typename Iterator>
 class safe_iterator:
-  public detail::iter_adaptor<safe_iterator<Iterator,Container>,Iterator>,
+  public detail::iter_adaptor<safe_iterator<Iterator>,Iterator>,
   public detail::safe_iterator_base
 {
   typedef detail::iter_adaptor<safe_iterator,Iterator> super;
   typedef detail::safe_iterator_base                   safe_super;
 
 public:
-  typedef Container                                    container_type;
   typedef typename Iterator::reference                 reference;
   typedef typename Iterator::difference_type           difference_type;
 
   safe_iterator(){}
-  explicit safe_iterator(safe_container<container_type>* cont_):
+  explicit safe_iterator(safe_container<safe_iterator>* cont_):
     safe_super(cont_){}
   template<typename T0>
-  safe_iterator(const T0& t0,safe_container<container_type>* cont_):
+  safe_iterator(const T0& t0,safe_container<safe_iterator>* cont_):
     super(Iterator(t0)),safe_super(cont_){}
   template<typename T0,typename T1>
   safe_iterator(
-    const T0& t0,const T1& t1,safe_container<container_type>* cont_):
+    const T0& t0,const T1& t1,safe_container<safe_iterator>* cont_):
     super(Iterator(t0,t1)),safe_super(cont_){}
   safe_iterator(const safe_iterator& x):super(x),safe_super(x){}
 
@@ -528,12 +545,11 @@ public:
     return *this;
   }
 
-  const container_type* owner()const
+  const safe_container<safe_iterator>* owner()const
   {
     return
-      static_cast<const container_type*>(
-        static_cast<const safe_container<container_type>*>(
-          this->safe_super::owner()));
+      static_cast<const safe_container<safe_iterator>*>(
+        this->safe_super::owner());
   }
 
   /* get_node is not to be used by the user */
@@ -624,21 +640,28 @@ private:
 #endif
 };
 
-template<typename Container>
+template<typename Iterator>
 class safe_container:public detail::safe_container_base
 {
   typedef detail::safe_container_base super;
 
+  detail::any_container_view<Iterator> view;
+
 public:
+  template<typename Container>
+  safe_container(const Container& c):view(c){}
+
+  const void* container()const{return view.container();}
+  Iterator    begin()const{return view.begin();}
+  Iterator    end()const{return view.end();}
+
   void detach_dereferenceable_iterators()
   {
-    typedef typename Container::iterator iterator;
-
-    iterator end_=static_cast<Container*>(this)->end();
-    iterator *prev_,*next_;
+    Iterator end_=view.end();
+    Iterator *prev_,*next_;
     for(
-      prev_=static_cast<iterator*>(&this->header);
-      (next_=static_cast<iterator*>(prev_->next))!=0;){
+      prev_=static_cast<Iterator*>(&this->header);
+      (next_=static_cast<Iterator*>(prev_->next))!=0;){
       if(*next_!=end_){
         prev_->next=next_->next;
         next_->cont=0;
@@ -647,7 +670,7 @@ public:
     }
   }
 
-  void swap(safe_container<Container>& x)
+  void swap(safe_container<Iterator>& x)
   {
     super::swap(x);
   }
@@ -659,9 +682,9 @@ public:
 
 #if !defined(BOOST_MULTI_INDEX_DISABLE_SERIALIZATION)
 namespace serialization{
-template<typename Iterator,typename Container>
+template<typename Iterator>
 struct version<
-  boost::multi_index::safe_mode::safe_iterator<Iterator,Container>
+  boost::multi_index::safe_mode::safe_iterator<Iterator>
 >
 {
   BOOST_STATIC_CONSTANT(
diff --git a/include/boost/multi_index/hashed_index.hpp b/include/boost/multi_index/hashed_index.hpp
index aa40dfb..a2e50b5 100644
--- a/include/boost/multi_index/hashed_index.hpp
+++ b/include/boost/multi_index/hashed_index.hpp
@@ -89,12 +89,6 @@ template<
 >
 class hashed_index:
   BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS SuperMeta::type
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  ,public safe_mode::safe_container<
-    hashed_index<KeyFromValue,Hash,Pred,SuperMeta,TagList,Category> >
-#endif
-
 { 
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
@@ -155,8 +149,7 @@ public:
     hashed_index_iterator<
       index_node_type,bucket_array_type,
       Category,
-      hashed_index_global_iterator_tag>,
-    hashed_index>                                iterator;
+      hashed_index_global_iterator_tag> >        iterator;
 #else
   typedef hashed_index_iterator<
     index_node_type,bucket_array_type,
@@ -198,8 +191,7 @@ protected:
 
 private:
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef safe_mode::safe_container<
-    hashed_index>                             safe_super;
+  typedef safe_mode::safe_container<iterator> safe_container;
 #endif
 
   typedef typename call_traits<value_type>::param_type value_param_type;
@@ -757,6 +749,11 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     eq_(tuples::get<3>(args_list.get_head())),
     buckets(al,header()->impl(),tuples::get<0>(args_list.get_head())),
     mlf(1.0f)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
     calculate_max_load();
   }
@@ -764,17 +761,17 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
   hashed_index(
     const hashed_index<KeyFromValue,Hash,Pred,SuperMeta,TagList,Category>& x):
     super(x),
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super(),
-#endif
-
     key(x.key),
     hash_(x.hash_),
     eq_(x.eq_),
     buckets(x.get_allocator(),header()->impl(),x.buckets.size()),
     mlf(x.mlf),
     max_load(x.max_load)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
     /* Copy ctor just takes the internal configuration objects from x. The rest
      * is done in subsequent call to copy_().
@@ -785,16 +782,16 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     const hashed_index<KeyFromValue,Hash,Pred,SuperMeta,TagList,Category>& x,
     do_not_copy_elements_tag):
     super(x,do_not_copy_elements_tag()),
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super(),
-#endif
-
     key(x.key),
     hash_(x.hash_),
     eq_(x.eq_),
     buckets(x.get_allocator(),header()->impl(),0),
     mlf(1.0f)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
      calculate_max_load();
   }
@@ -807,12 +804,12 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   iterator make_iterator(index_node_type* node)
   {
-    return iterator(node,this);
+    return iterator(node,&safe);
   }
 
   const_iterator make_iterator(index_node_type* node)const
   {
-    return const_iterator(node,const_cast<hashed_index*>(this));
+    return const_iterator(node,const_cast<safe_container*>(&safe));
   }
 #else
   iterator make_iterator(index_node_type* node)
@@ -1015,7 +1012,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     buckets.clear(header()->impl());
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::detach_dereferenceable_iterators();
+    safe.detach_dereferenceable_iterators();
 #endif
   }
 
@@ -1032,7 +1029,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     std::swap(max_load,x.max_load);
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_(x,swap_allocators);
@@ -1046,7 +1043,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     std::swap(max_load,x.max_load);
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_elements_(x);
@@ -1776,7 +1773,11 @@ private:
   bucket_array_type            buckets;
   float                        mlf;
   size_type                    max_load;
-      
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+  safe_container               safe;
+#endif
+
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
 #pragma parse_mfunc_templ reset
diff --git a/include/boost/multi_index/random_access_index.hpp b/include/boost/multi_index/random_access_index.hpp
index abf7db3..586460f 100644
--- a/include/boost/multi_index/random_access_index.hpp
+++ b/include/boost/multi_index/random_access_index.hpp
@@ -81,12 +81,6 @@ namespace detail{
 template<typename SuperMeta,typename TagList>
 class random_access_index:
   BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS SuperMeta::type
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  ,public safe_mode::safe_container<
-    random_access_index<SuperMeta,TagList> >
-#endif
-
 { 
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
@@ -127,8 +121,7 @@ public:
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   typedef safe_mode::safe_iterator<
-    rnd_node_iterator<index_node_type>,
-    random_access_index>                         iterator;
+    rnd_node_iterator<index_node_type> >        iterator;
 #else
   typedef rnd_node_iterator<index_node_type>    iterator;
 #endif
@@ -175,8 +168,7 @@ protected:
 
 private:
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef safe_mode::safe_container<
-    random_access_index>                      safe_super;
+  typedef safe_mode::safe_container<iterator> safe_container;
 #endif
 
   typedef typename call_traits<
@@ -760,17 +752,22 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     const ctor_args_list& args_list,const allocator_type& al):
     super(args_list.get_tail(),al),
     ptrs(al,header()->impl(),0)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+    
   {
   }
 
   random_access_index(const random_access_index<SuperMeta,TagList>& x):
     super(x),
+    ptrs(x.get_allocator(),header()->impl(),x.size())
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super(),
+    ,safe(*this)
 #endif
 
-    ptrs(x.get_allocator(),header()->impl(),x.size())
   {
     /* The actual copying takes place in subsequent call to copy_().
      */
@@ -779,12 +776,12 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
   random_access_index(
     const random_access_index<SuperMeta,TagList>& x,do_not_copy_elements_tag):
     super(x,do_not_copy_elements_tag()),
+    ptrs(x.get_allocator(),header()->impl(),0)
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super(),
+    ,safe(*this)
 #endif
 
-    ptrs(x.get_allocator(),header()->impl(),0)
   {
   }
 
@@ -795,9 +792,9 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   iterator       make_iterator(index_node_type* node)
-    {return iterator(node,this);}
+    {return iterator(node,&safe);}
   const_iterator make_iterator(index_node_type* node)const
-    {return const_iterator(node,const_cast<random_access_index*>(this));}
+    {return const_iterator(node,const_cast<safe_container*>(&safe));}
 #else
   iterator       make_iterator(index_node_type* node){return iterator(node);}
   const_iterator make_iterator(index_node_type* node)const
@@ -868,7 +865,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     ptrs.clear();
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::detach_dereferenceable_iterators();
+    safe.detach_dereferenceable_iterators();
 #endif
   }
 
@@ -879,7 +876,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     ptrs.swap(x.ptrs,swap_allocators);
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_(x,swap_allocators);
@@ -890,7 +887,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     ptrs.swap(x.ptrs);
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_elements_(x);
@@ -1208,7 +1205,11 @@ private:
     relocate(position,begin()+n,end());
   }
 
-  ptr_array ptrs;
+  ptr_array      ptrs;
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+  safe_container safe;
+#endif
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
diff --git a/include/boost/multi_index/sequenced_index.hpp b/include/boost/multi_index/sequenced_index.hpp
index 57414c5..ccb4b04 100644
--- a/include/boost/multi_index/sequenced_index.hpp
+++ b/include/boost/multi_index/sequenced_index.hpp
@@ -71,12 +71,6 @@ namespace detail{
 template<typename SuperMeta,typename TagList>
 class sequenced_index:
   BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS SuperMeta::type
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  ,public safe_mode::safe_container<
-    sequenced_index<SuperMeta,TagList> >
-#endif
-
 { 
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
@@ -114,8 +108,7 @@ public:
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   typedef safe_mode::safe_iterator<
-    bidir_node_iterator<index_node_type>,
-    sequenced_index>                             iterator;
+    bidir_node_iterator<index_node_type> >       iterator;
 #else
   typedef bidir_node_iterator<index_node_type>   iterator;
 #endif
@@ -162,8 +155,7 @@ protected:
 
 private:
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef safe_mode::safe_container<
-    sequenced_index>                          safe_super;
+  typedef safe_mode::safe_container<iterator> safe_container;
 #endif
 
   typedef typename call_traits<value_type>::param_type value_param_type;
@@ -674,6 +666,11 @@ public:
 BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
   sequenced_index(const ctor_args_list& args_list,const allocator_type& al):
     super(args_list.get_tail(),al)
+
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+    ,safe(*this)
+#endif
+
   {
     empty_initialize();
   }
@@ -682,7 +679,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     super(x)
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    ,safe_super()
+    ,safe(*this)
 #endif
 
   {
@@ -694,7 +691,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     super(x,do_not_copy_elements_tag())
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    ,safe_super()
+    ,safe(*this)
 #endif
 
   {
@@ -708,9 +705,9 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
   iterator       make_iterator(index_node_type* node)
-    {return iterator(node,this);}
+    {return iterator(node,&safe);}
   const_iterator make_iterator(index_node_type* node)const
-    {return const_iterator(node,const_cast<sequenced_index*>(this));}
+    {return const_iterator(node,const_cast<safe_container*>(&safe));}
 #else
   iterator       make_iterator(index_node_type* node){return iterator(node);}
   const_iterator make_iterator(index_node_type* node)const
@@ -781,7 +778,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     empty_initialize();
 
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::detach_dereferenceable_iterators();
+    safe.detach_dereferenceable_iterators();
 #endif
   }
 
@@ -790,7 +787,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
     sequenced_index<SuperMeta,TagList>& x,BoolConstant swap_allocators)
   {
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_(x,swap_allocators);
@@ -799,7 +796,7 @@ BOOST_MULTI_INDEX_PROTECTED_IF_MEMBER_TEMPLATE_FRIENDS:
   void swap_elements_(sequenced_index<SuperMeta,TagList>& x)
   {
 #if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-    safe_super::swap(x);
+    safe.swap(x.safe);
 #endif
 
     super::swap_elements_(x);
@@ -1118,6 +1115,10 @@ private:
     }
   }
 
+#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
+  safe_container safe;
+#endif
+
 #if defined(BOOST_MULTI_INDEX_ENABLE_INVARIANT_CHECKING)&&\
     BOOST_WORKAROUND(__MWERKS__,<=0x3003)
 #pragma parse_mfunc_templ reset
diff --git a/include/boost/multi_index_container.hpp b/include/boost/multi_index_container.hpp
index bd5a847..3be5d3c 100644
--- a/include/boost/multi_index_container.hpp
+++ b/include/boost/multi_index_container.hpp
@@ -489,9 +489,7 @@ public:
 #endif
 
     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-    BOOST_MULTI_INDEX_CHECK_IS_OWNER(
-      it,static_cast<typename IteratorType::container_type&>(*this));
-
+    BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,*this);
     return index_type::make_iterator(
       static_cast<final_node_type*>(it.get_node()));
   }
@@ -508,8 +506,7 @@ public:
 #endif
 
     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-    BOOST_MULTI_INDEX_CHECK_IS_OWNER(
-      it,static_cast<const typename IteratorType::container_type&>(*this));
+    BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,*this);
     return index_type::make_iterator(
       static_cast<final_node_type*>(it.get_node()));
   }
@@ -541,8 +538,7 @@ public:
 #endif
 
     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-    BOOST_MULTI_INDEX_CHECK_IS_OWNER(
-      it,static_cast<typename IteratorType::container_type&>(*this));
+    BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,*this);
     return index_type::make_iterator(
       static_cast<final_node_type*>(it.get_node()));
   }
@@ -559,8 +555,7 @@ public:
 #endif
 
     BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-    BOOST_MULTI_INDEX_CHECK_IS_OWNER(
-      it,static_cast<const typename IteratorType::container_type&>(*this));
+    BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,*this);
     return index_type::make_iterator(
       static_cast<final_node_type*>(it.get_node()));
   }
@@ -1362,14 +1357,7 @@ project(
 #endif
 
   BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef detail::converter<
-    multi_index_type,
-    BOOST_DEDUCED_TYPENAME IteratorType::container_type> converter;
-  BOOST_MULTI_INDEX_CHECK_IS_OWNER(it,converter::index(m));
-#endif
-
+  BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,m);
   return detail::converter<multi_index_type,index_type>::iterator(
     m,static_cast<typename multi_index_type::final_node_type*>(it.get_node()));
 }
@@ -1398,14 +1386,7 @@ project(
 #endif
 
   BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef detail::converter<
-    multi_index_type,
-    BOOST_DEDUCED_TYPENAME IteratorType::container_type> converter;
-  BOOST_MULTI_INDEX_CHECK_IS_OWNER(it,converter::index(m));
-#endif
-
+  BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,m);
   return detail::converter<multi_index_type,index_type>::const_iterator(
     m,static_cast<typename multi_index_type::final_node_type*>(it.get_node()));
 }
@@ -1448,14 +1429,7 @@ project(
 #endif
 
   BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef detail::converter<
-    multi_index_type,
-    BOOST_DEDUCED_TYPENAME IteratorType::container_type> converter;
-  BOOST_MULTI_INDEX_CHECK_IS_OWNER(it,converter::index(m));
-#endif
-
+  BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,m);
   return detail::converter<multi_index_type,index_type>::iterator(
     m,static_cast<typename multi_index_type::final_node_type*>(it.get_node()));
 }
@@ -1485,14 +1459,7 @@ project(
 #endif
 
   BOOST_MULTI_INDEX_CHECK_VALID_ITERATOR(it);
-
-#if defined(BOOST_MULTI_INDEX_ENABLE_SAFE_MODE)
-  typedef detail::converter<
-    multi_index_type,
-    BOOST_DEDUCED_TYPENAME IteratorType::container_type> converter;
-  BOOST_MULTI_INDEX_CHECK_IS_OWNER(it,converter::index(m));
-#endif
-
+  BOOST_MULTI_INDEX_CHECK_BELONGS_IN_SOME_INDEX(it,m);
   return detail::converter<multi_index_type,index_type>::const_iterator(
     m,static_cast<typename multi_index_type::final_node_type*>(it.get_node()));
 }