diff --git a/Makefile b/Makefile
index 5eab9d5..17bbe69 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,14 @@
 # Makefile for the open-source release of adventure 2.5
-
-LIBS=-lrt
+ifeq ($(OS),Windows_NT)
+	LIBS=-lrt
+else
+	UNAME_S := $(shell uname -s)
+	ifeq ($(UNAME_S),Darwin)
+		LIBS=
+	else
+		LIBS=-lrt
+	endif
+endif
 OBJS=main.o init.o actions1.o actions2.o score.o misc.o database.o
 SOURCES=$(OBJS:.o=.c) COPYING NEWS README TODO advent.text control