diff --git a/modules/juce_core/text/juce_String.cpp b/modules/juce_core/text/juce_String.cpp
index 55dea1be34..ce93d7a9ff 100644
--- a/modules/juce_core/text/juce_String.cpp
+++ b/modules/juce_core/text/juce_String.cpp
@@ -851,6 +851,7 @@ JUCE_API String JUCE_CALLTYPE operator+ (wchar_t s1, const String& s2)        {
 JUCE_API String JUCE_CALLTYPE operator+ (String s1, const String& s2)         { return s1 += s2; }
 JUCE_API String JUCE_CALLTYPE operator+ (String s1, const char* s2)           { return s1 += s2; }
 JUCE_API String JUCE_CALLTYPE operator+ (String s1, const wchar_t* s2)        { return s1 += s2; }
+JUCE_API String JUCE_CALLTYPE operator+ (String s1, const std::string& s2)    { return s1 += s2.c_str(); }
 
 JUCE_API String JUCE_CALLTYPE operator+ (String s1, char s2)                  { return s1 += s2; }
 JUCE_API String JUCE_CALLTYPE operator+ (String s1, wchar_t s2)               { return s1 += s2; }
@@ -868,6 +869,7 @@ JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, const char* s2)        {
 JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, const wchar_t* s2)     { return s1 += s2; }
 JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, const String& s2)      { return s1 += s2; }
 JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, StringRef s2)          { return s1 += s2; }
+JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, const std::string& s2) { return s1 += s2.c_str(); }
 
 JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, uint8  number)         { return s1 += (int) number; }
 JUCE_API String& JUCE_CALLTYPE operator<< (String& s1, short  number)         { return s1 += (int) number; }
diff --git a/modules/juce_core/text/juce_String.h b/modules/juce_core/text/juce_String.h
index 49686752fb..ae5937ed06 100644
--- a/modules/juce_core/text/juce_String.h
+++ b/modules/juce_core/text/juce_String.h
@@ -1304,6 +1304,8 @@ JUCE_API String JUCE_CALLTYPE operator+ (String string1, const char* string2);
 /** Concatenates two strings. */
 JUCE_API String JUCE_CALLTYPE operator+ (String string1, const wchar_t* string2);
 /** Concatenates two strings. */
+JUCE_API String JUCE_CALLTYPE operator+ (String string1, const std::string& string2);
+/** Concatenates two strings. */
 JUCE_API String JUCE_CALLTYPE operator+ (String string1, char characterToAppend);
 /** Concatenates two strings. */
 JUCE_API String JUCE_CALLTYPE operator+ (String string1, wchar_t characterToAppend);
@@ -1330,6 +1332,8 @@ JUCE_API String& JUCE_CALLTYPE operator<< (String& string1, const wchar_t* strin
 JUCE_API String& JUCE_CALLTYPE operator<< (String& string1, const String& string2);
 /** Appends a string to the end of the first one. */
 JUCE_API String& JUCE_CALLTYPE operator<< (String& string1, StringRef string2);
+/** Appends a string to the end of the first one. */
+JUCE_API String& JUCE_CALLTYPE operator<< (String& string1, const std::string& string2);
 
 /** Appends a decimal number to the end of a string. */
 JUCE_API String& JUCE_CALLTYPE operator<< (String& string1, uint8 number);