--- /dev/null
+++ b/include/makeinclude/platform_macosx_monterey.GNU
@@ -0,0 +1,2 @@
+include $(ACE_ROOT)/include/makeinclude/platform_macosx_bigsur.GNU
+

--- a/include/makeinclude/platform_macosx.GNU
+++ b/include/makeinclude/platform_macosx.GNU
@@ -24,6 +24,9 @@
 MACOS_CODENAME_VER_11_1   := bigsur
 MACOS_CODENAME_VER_11_2   := bigsur
 MACOS_CODENAME_VER_11_latest := bigsur
+MACOS_CODENAME_VER_12_0   := monterey
+MACOS_CODENAME_VER_12_1   := monterey
+MACOS_CODENAME_VER_12_latest := monterey
 
 MACOS_CODENAME = $(MACOS_CODENAME_VER_$(MACOS_MAJOR_VERSION)_$(MACOS_MINOR_VERSION))
 
@@ -42,6 +45,12 @@ else ifeq ($(MACOS_MAJOR_VERSION), 11)
     ## just use the latest known version
     MACOS_CODENAME = $(MACOS_CODENAME_VER_11_latest)
   endif
+else ifeq ($(MACOS_MAJOR_VERSION),12)
+  ifeq ($(shell test $(MACOS_MINOR_VERSION) -gt 1; echo $$?),0)
+    ## if the detected version is greater than the latest know version,
+    ## just use the latest known version
+    MACOS_CODENAME = $(MACOS_CODENAME_VER_12_latest)
+  endif
 else
   ## Unsupported major version
   $(error Unsupported MacOS version $(MACOS_RELEASE_VERSION))