diff --git a/include/CLI/Ini.hpp b/include/CLI/Ini.hpp
index 756e971c..baeae521 100644
--- a/include/CLI/Ini.hpp
+++ b/include/CLI/Ini.hpp
@@ -6,6 +6,7 @@
 #include <fstream>
 #include <string>
 #include <iostream>
+#include <algorithm>
 
 #include "CLI/StringTools.hpp"
 
diff --git a/include/CLI/StringTools.hpp b/include/CLI/StringTools.hpp
index c4372d34..fff1f03e 100644
--- a/include/CLI/StringTools.hpp
+++ b/include/CLI/StringTools.hpp
@@ -8,6 +8,7 @@
 #include <iomanip>
 #include <locale>
 #include <type_traits>
+#include <algorithm>
 
 namespace CLI {
 namespace detail {