diff --git a/Makefile b/Makefile
index 15241116046e..31dc12134599 100644
--- a/Makefile
+++ b/Makefile
@@ -73,7 +73,7 @@ TGTS=	all all-man buildenv buildkernel buildworld check-old checkdpadd \
 	hierarchy install installcheck installkernel installkernel.debug\
 	reinstallkernel reinstallkernel.debug installworld \
 	kernel-toolchain libraries lint maninstall \
-	obj objlink regress rerelease tags toolchain update \
+	obj objlink regress rerelease showconfig tags toolchain update \
 	_worldtmp _legacy _bootstrap-tools _cleanobj _obj \
 	_build-tools _cross-tools _includes _libraries _depend \
 	build32 distribute32 install32
diff --git a/Makefile.inc1 b/Makefile.inc1
index ea030e5eb4ae..f7d2ec507fd0 100644
--- a/Makefile.inc1
+++ b/Makefile.inc1
@@ -1175,3 +1175,8 @@ check-old: check-old-files check-old-libs check-old-dirs
 
 .endif
 
+#
+# showconfig - show build configuration.
+#
+showconfig:
+	@${MAKE} -n -f bsd.own.mk -V dummy -dg1 | grep ^MK_ | sort