diff --git a/include/Makefile b/include/Makefile
index 45ee3caa8bee..7ed6b4150118 100644
--- a/include/Makefile
+++ b/include/Makefile
@@ -2,6 +2,9 @@
 # $FreeBSD$
 #
 # Doing a make install builds /usr/include
+#
+# The ``rm -rf''s used below are safe because rm doesn't follow symbolic
+# links.
 
 CLEANFILES= osreldate.h version vers.c
 SUBDIR= rpcsvc
@@ -32,14 +35,24 @@ MFILES=	float.h floatingpoint.h stdarg.h varargs.h
 # posix4/aio.h conflicts with dysons and isn't installed:
 PFILES=	mqueue.h sched.h semaphore.h # aio.h
 
-SFILES=	joystick.h soundcard.h
+# Only for default SHARED=copies case
+SFILES=	soundcard.h joystick.h
 
 LFILES=	aio.h errno.h fcntl.h inttypes.h linker_set.h poll.h syslog.h \
 	termios.h ucontext.h
 
-LDIRS=	cam cam/scsi isofs/cd9660 msdosfs net netatalk netatm netgraph \
-	netinet netinet6 netipx netkey netncp netns nfs ntfs nwfs pccard \
-	posix4 sys ufs/ffs ufs/mfs ufs/ufs vm
+LDIRS=	cam msdosfs net netatalk netatm netgraph netinet netinet6 \
+	netipx netkey netncp netns nfs ntfs nwfs pccard posix4 sys vm
+
+LNOHEADERDIRS=	isofs ufs
+LSUBDIRS=	isofs/cd9660 ufs/ffs ufs/mfs ufs/ufs cam/scsi
+
+# Define SHARED to indicate whether you want symbolic links to the system
+# source (``symlinks''), or a separate copy (``copies'').  ``symlinks'' is
+# probably only useful for developers and should be avoided if you do not
+# wish to tie your /usr/include and /usr/src together.
+#SHARED=	symlinks
+SHARED?=	copies
 
 all:	osreldate.h
 
@@ -52,31 +65,23 @@ osreldate.h:	${.CURDIR}/../sys/conf/newvers.sh \
 	echo \#'undef __FreeBSD_version' >> osreldate.h;	\
 	echo \#'define __FreeBSD_version' $$RELDATE >> osreldate.h
 
-beforeinstall:
-	${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 ${.OBJDIR}/osreldate.h \
-		${DESTDIR}/usr/include
+beforeinstall: ${SHARED}
+	@rm -f ${DESTDIR}/usr/include/timepps.h
 	cd ${.CURDIR}; \
-		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 ${FILES} \
-			${DESTDIR}/usr/include
+		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 \
+		${FILES} ${DESTDIR}/usr/include
 	cd ${.CURDIR}/arpa; \
-		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 ${ARPAFILES} \
-			${DESTDIR}/usr/include/arpa
+		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 \
+		${ARPAFILES} ${DESTDIR}/usr/include/arpa
 	cd ${.CURDIR}/protocols; \
-		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 ${PROTOFILES} \
-			${DESTDIR}/usr/include/protocols
+		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 \
+		${PROTOFILES} ${DESTDIR}/usr/include/protocols
 	cd ${.CURDIR}/rpc; \
-		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 ${RPCFILES} \
-			${DESTDIR}/usr/include/rpc
-.for i in ${LDIRS}
-	cd ${.CURDIR}/../sys; \
-		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 $i/*.h \
-			${DESTDIR}/usr/include/$i
-.endfor
-.if exists(${.CURDIR}/../sys/${MACHINE_ARCH}/include)
-	cd ${.CURDIR}/../sys/${MACHINE_ARCH}/include; \
-		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 *.h \
-			${DESTDIR}/usr/include/machine
-.endif
+		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 \
+		${RPCFILES} ${DESTDIR}/usr/include/rpc
+	${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 \
+		${.OBJDIR}/osreldate.h \
+		${DESTDIR}/usr/include
 .for i in ${LFILES}
 	ln -sf sys/$i ${DESTDIR}/usr/include/$i
 .endfor
@@ -86,8 +91,36 @@ beforeinstall:
 .for i in ${PFILES}
 	ln -sf posix4/$i ${DESTDIR}/usr/include/$i
 .endfor
+
+copies:
+.for i in ${LDIRS} ${LNOHEADERDIRS} machine
+	if [ -h ${DESTDIR}/usr/include/$i ]; then \
+		rm -f ${DESTDIR}/usr/include/$i; \
+	fi
+.endfor
+	mtree -deU -f ${.CURDIR}/../etc/mtree/BSD.include.dist \
+		-p ${DESTDIR}/usr/include
+.for i in ${LDIRS} ${LSUBDIRS}
+	cd ${.CURDIR}/../sys; \
+		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 $i/*.h \
+		${DESTDIR}/usr/include/$i
+.endfor
+.if exists(${.CURDIR}/../sys/${MACHINE_ARCH}/include)
+	cd ${.CURDIR}/../sys/${MACHINE_ARCH}/include; \
+		${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 *.h \
+		${DESTDIR}/usr/include/machine
+.endif
 .for i in ${SFILES}
 	ln -sf ../sys/$i ${DESTDIR}/usr/include/machine/$i
 .endfor
 
+symlinks:
+	@${ECHO} "Setting up symlinks to kernel source tree..."
+.for i in ${LDIRS} ${LNOHEADERDIRS}
+	rm -rf ${DESTDIR}/usr/include/$i
+	ln -s ../../sys/$i ${DESTDIR}/usr/include/$i
+.endfor
+	rm -rf ${DESTDIR}/usr/include/machine
+	ln -s ../../sys/${MACHINE_ARCH}/include ${DESTDIR}/usr/include/machine
+
 .include <bsd.prog.mk>
diff --git a/share/examples/Makefile b/share/examples/Makefile
index 1e07279094c2..3591fc648403 100644
--- a/share/examples/Makefile
+++ b/share/examples/Makefile
@@ -8,10 +8,14 @@ DDIR=	${DESTDIR}/usr/share/examples
 
 NOOBJ=	noobj
 
+# Define SHARED to indicate whether you want symbolic links to the system
+# source (``symlinks''), or a separate copy (``copies''); (latter useful
+# in environments where it's not possible to keep /sys publicly readable)
+SHARED?=	copies
+
 all clean cleandir depend lint tags:
 
-beforeinstall: copies
-	(cd ${.CURDIR}/../../etc; ${MAKE} etc-examples)
+beforeinstall: etc-examples ${SHARED}
 
 .for dir in ${DIRS}
 FILES!=	find -L ${dir} \( -name CVS -prune \) -o -type f -print
@@ -21,4 +25,14 @@ copies::
 .endfor
 .endfor
 
+.for dir in ${DIRS}
+symlinks::
+	rm -rf ${DDIR}/${dir}; ln -s ${.CURDIR}/${dir} ${DDIR}
+.endfor
+
+etc-examples:
+.if ${SHARED} != "symlinks"
+	(cd ${.CURDIR}/../../etc; ${MAKE} etc-examples)
+.endif
+
 .include <bsd.prog.mk>