--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,4 @@
-appdefaultdir=$(shell pkg-config --variable=appdefaultdir xt)
-datarootdir=$(shell pkg-config --variable=datarootdir xt)
+appdefaultdir = $(shell $(PKG_CONFIG) --variable=appdefaultdir xt)
 
 SUBDIRS = .
 bin_PROGRAMS = xvkbd
@@ -17,11 +16,12 @@
 	[ which ad2c > /dev/null ] || ad2c XVkbd-common.ad > XVkbd-common.h
 
 install-data-hook:
+	[ -d $(DESTDIR)/$(appdefaultdir)/xvkbd/ ] || mkdir $(DESTDIR)/$(appdefaultdir)/xvkbd/
 	for file in *.ad; do \
-		$(INSTALL_DATA) $$file $(appdefaultdir)/$${file%.ad}; \
+		$(INSTALL_DATA) $$file $(DESTDIR)/$(appdefaultdir)/$${file%.ad}; \
 	done
-	[ -d $(datarootdir)/xvkbd/ ] || mkdir $(datarootdir)/xvkbd/
-	$(INSTALL_DATA) words.english $(datarootdir)/xvkbd/words.english
+	[ -d $(DESTDIR)/$(datarootdir)/xvkbd/ ] || mkdir $(DESTDIR)/$(datarootdir)/xvkbd/
+	$(INSTALL_DATA) words.english $(DESTDIR)/$(datarootdir)/xvkbd/words.english
 
 EXTRA_DIST = XVkbd-common.h *.ad *.xbm xvkbd.man README ChangeLog Imakefile words.english