diff --git a/Makefile b/Makefile
index b6b84f9..23b31c3 100644
--- a/Makefile
+++ b/Makefile
@@ -39,7 +39,7 @@ DYNAMIC_LIBRARY=libpri.so.1.0
 STATIC_OBJS=copy_string.o pri.o q921.o prisched.o q931.o pri_facility.o
 DYNAMIC_OBJS=copy_string.lo pri.lo q921.lo prisched.lo q931.lo pri_facility.lo
 CFLAGS=-Wall -Werror -Wstrict-prototypes -Wmissing-prototypes -g $(ALERTING) $(LIBPRI_COUNTERS)
-INSTALL_PREFIX?=
+INSTALL_PREFIX=$(DESTDIR)
 INSTALL_BASE=/usr
 SOFLAGS = -Wl,-hlibpri.so.1.0
 LDCONFIG = /sbin/ldconfig