--- a/Makefile
+++ b/Makefile
@@ -102,9 +102,11 @@
     endif
 endif
 
-ifndef PREFIX
-    PREFIX=/usr
-endif
+DESTDIR?= ""
+prefix?= "/usr"
+bindir?= "$(prefix)/bin"
+BINDIR=$(bindir)
+PREFIX=$(prefix)
 
 ifndef INCLUDE_FOR_LIB
     INCLUDE_FOR_LIB=-Ilib -Iexternals/simplecpp -Iexternals/tinyxml
@@ -117,8 +119,6 @@
 ifndef INCLUDE_FOR_TEST
     INCLUDE_FOR_TEST=-Ilib -Icli -Iexternals/simplecpp -Iexternals/tinyxml
 endif
-
-BIN=$(DESTDIR)$(PREFIX)/bin
 
 # For 'make man': sudo apt-get install xsltproc docbook-xsl docbook-xml on Linux
 DB2MAN?=/usr/share/sgml/docbook/stylesheet/xsl/nwalsh/manpages/docbook.xsl
@@ -287,11 +287,11 @@
 	ctags -R --exclude=doxyoutput --exclude=test/cfg cli externals gui lib test
 
 install: cppcheck
-	install -d ${BIN}
-	install cppcheck ${BIN}
-	install addons/*.py ${BIN}
-	install addons/*/*.py ${BIN}
-	install htmlreport/cppcheck-htmlreport ${BIN}
+	install -d ${DESTDIR}${BINDIR}
+	install cppcheck ${DESTDIR}${BINDIR}
+	install addons/*.py ${DESTDIR}${BINDIR}
+	install addons/*/*.py ${DESTDIR}${BINDIR}
+	install htmlreport/cppcheck-htmlreport ${DESTDIR}${BINDIR}
 ifdef CFGDIR 
 	install -d ${DESTDIR}${CFGDIR}
 	install -m 644 cfg/* ${DESTDIR}${CFGDIR}