diff --git a/Source/DiabloUI/selyesno.cpp b/Source/DiabloUI/selyesno.cpp
index 6559ce716..46819915f 100644
--- a/Source/DiabloUI/selyesno.cpp
+++ b/Source/DiabloUI/selyesno.cpp
@@ -5,6 +5,7 @@
 #include "DiabloUI/text.h"
 
 namespace devilution {
+namespace {
 
 bool selyesno_endMenu;
 bool selyesno_value;
@@ -45,6 +46,8 @@ void selyesno_Esc()
 	selyesno_endMenu = true;
 }
 
+} // namespace
+
 bool UiSelHeroYesNoDialog(const char *title, const char *body)
 {
 	LoadBackgroundArt("ui_art\\black.pcx");
diff --git a/Source/DiabloUI/selyesno.h b/Source/DiabloUI/selyesno.h
index 3e2ae70d3..81a8aea12 100644
--- a/Source/DiabloUI/selyesno.h
+++ b/Source/DiabloUI/selyesno.h
@@ -3,8 +3,5 @@
 namespace devilution {
 
 bool UiSelHeroYesNoDialog(const char *title, const char *body);
-void selyesno_Free();
-void selyesno_Select(int value);
-void selyesno_Esc();
 
 } // namespace devilution