diff --git a/Makefile b/Makefile
index 5e749d1..e9acc32 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,12 @@ CFLAGS = -O3 -std=c++11 -fopenmp -mpopcnt
 # define any directories containing header files other than /usr/include
 INCLUDES = -Isrc/ISSL/include
 
-all : isslScoreOfftargets isslCreateIndex
+all : bin_check isslScoreOfftargets isslCreateIndex
+
+bin_check:
+	@if [ ! -d bin ]; then \
+		mkdir bin; \
+	fi
 
 isslScoreOfftargets : src/ISSL/isslScoreOfftargets.cpp
 	$(CC) $(CFLAGS) $(INCLUDES) -o bin/$@ $^