diff --git a/include/rapidjson/internal/biginteger.h b/include/rapidjson/internal/biginteger.h
index dea30cf..06a442b 100644
--- a/include/rapidjson/internal/biginteger.h
+++ b/include/rapidjson/internal/biginteger.h
@@ -23,7 +23,7 @@
 
 #include "../rapidjson.h"
 
-namespace rapidjson {
+RAPIDJSON_NAMESPACE_BEGIN
 namespace internal {
 
 class BigInteger {
@@ -285,6 +285,6 @@ private:
 };
 
 } // namespace internal
-} // namespace rapidjson
+RAPIDJSON_NAMESPACE_END
 
 #endif // RAPIDJSON_BIGINTEGER_H_
diff --git a/include/rapidjson/internal/diyfp.h b/include/rapidjson/internal/diyfp.h
index a8e47e1..174b9fa 100644
--- a/include/rapidjson/internal/diyfp.h
+++ b/include/rapidjson/internal/diyfp.h
@@ -32,7 +32,7 @@
 #endif
 #endif
 
-namespace rapidjson {
+RAPIDJSON_NAMESPACE_BEGIN
 namespace internal {
 
 #ifdef __GNUC__
@@ -263,6 +263,6 @@ RAPIDJSON_DIAG_POP
 #endif
 
 } // namespace internal
-} // namespace rapidjson
+RAPIDJSON_NAMESPACE_END
 
 #endif // RAPIDJSON_DIYFP_H_
diff --git a/include/rapidjson/internal/ieee754.h b/include/rapidjson/internal/ieee754.h
index 41aea12..ab65cc9 100644
--- a/include/rapidjson/internal/ieee754.h
+++ b/include/rapidjson/internal/ieee754.h
@@ -23,7 +23,7 @@
 
 #include "../rapidjson.h"
 
-namespace rapidjson {
+RAPIDJSON_NAMESPACE_BEGIN
 namespace internal {
 
 class Double {
@@ -85,6 +85,6 @@ private:
 };
 
 } // namespace internal
-} // namespace rapidjson
+RAPIDJSON_NAMESPACE_END
 
 #endif // RAPIDJSON_IEEE754_
diff --git a/include/rapidjson/internal/strtod.h b/include/rapidjson/internal/strtod.h
index 9a4daea..1fc6050 100644
--- a/include/rapidjson/internal/strtod.h
+++ b/include/rapidjson/internal/strtod.h
@@ -27,7 +27,7 @@
 #include "diyfp.h"
 #include "pow10.h"
 
-namespace rapidjson {
+RAPIDJSON_NAMESPACE_BEGIN
 namespace internal {
 
 inline double FastPath(double significand, int exp) {
@@ -280,6 +280,6 @@ inline double StrtodFullPrecision(double d, int p, const char* decimals, size_t
 }
 
 } // namespace internal
-} // namespace rapidjson
+RAPIDJSON_NAMESPACE_END
 
 #endif // RAPIDJSON_STRTOD_