diff --git a/libexec/rc/rc.conf b/libexec/rc/rc.conf
--- a/libexec/rc/rc.conf
+++ b/libexec/rc/rc.conf
@@ -735,6 +735,7 @@
 ##############################################################
 jail_enable="NO"	# Set to NO to disable starting of any jails
 jail_conf="/etc/jail.conf"	# Configuration file for jail(8)
+jail_conf_dir="/etc/jail.conf.d"	# Configuration directory for jail(8)
 jail_confwarn="YES"	# Prevent warning about obsolete per-jail configuration
 jail_parallel_start="NO"	# Start jails in the background
 jail_list=""		# Space separated list of names of jails
diff --git a/libexec/rc/rc.d/jail b/libexec/rc/rc.d/jail
--- a/libexec/rc/rc.d/jail
+++ b/libexec/rc/rc.d/jail
@@ -455,12 +455,14 @@
 	_ALL)
 		command=$jail_program
 		rc_flags=$jail_flags
-		command_args="-f $jail_conf -c"
+		command_args='-f - -c'
 		if ! checkyesno jail_parallel_start; then
 			command_args="$command_args -p1"
 		fi
 		_tmp=`mktemp -t jail` || exit 3
-		if $command $rc_flags $command_args >> $_tmp 2>&1; then
+		if cat $jail_conf $jail_conf_dir/*.conf \
+		/etc/jail.*.conf 2>/dev/null | \
+		$command $rc_flags $command_args >> $_tmp 2>&1; then
 			$jail_jls jid name | while read _id _name; do
 				startmsg -n " $_name"
 				echo $_id > /var/run/jail_${_name}.id
@@ -485,10 +487,12 @@
 
 			eval rc_flags=\${jail_${_jv}_flags:-$jail_flags}
 			eval command=\${jail_${_jv}_program:-$jail_program}
-			command_args="-i -f $_conf -c $_j"
+			command_args="-i -f - -c $_j"
 			(
 				_tmp=`mktemp -t jail_${_j}` || exit 3
-				if $command $rc_flags $command_args \
+				if cat $jail_conf $_conf $jail_conf_dir/*.conf \
+				/etc/jail.*.conf 2>/dev/null | \
+				$command $rc_flags $command_args \
 				    >> $_tmp 2>&1 </dev/null; then
 					startmsg -n " ${_hostname:-${_j}}"
 					_jid=$($jail_jls -j $_j jid)
@@ -513,9 +517,11 @@
 
 			eval rc_flags=\${jail_${_jv}_flags:-$jail_flags}
 			eval command=\${jail_${_jv}_program:-$jail_program}
-			command_args="-i -f $_conf -c $_j"
+			command_args="-i -f - -c"
 			_tmp=`mktemp -t jail` || exit 3
-			if $command $rc_flags $command_args \
+			if (cat $_conf $jail_conf $jail_conf_dir/*.conf \
+			/etc/jail.*.conf 2>/dev/null | \
+			$command $rc_flags $command_args $_j) \
 			    >> $_tmp 2>&1 </dev/null; then
 				startmsg -n " ${_hostname:-${_j}}"
 				_jid=$($jail_jls -j $_j jid)
@@ -543,7 +549,7 @@
 	_ALL)
 		command=$jail_program
 		rc_flags=$jail_flags
-		command_args="-f $jail_conf -r"
+		command_args='-f - -r'
 		if checkyesno jail_reverse_stop; then
 			$jail_jls name | tail -r
 		else
@@ -551,6 +557,8 @@
 		fi | while read _j; do
 			echo -n " $_j"
 			_tmp=`mktemp -t jail` || exit 3
+			cat $jail_conf $jail_conf_dir/*.conf \
+			/etc/jail.*.conf 2>/dev/null | \
 			$command $rc_flags $command_args $_j >> $_tmp 2>&1
 			if $jail_jls -j $_j > /dev/null 2>&1; then
 				cat $_tmp
@@ -574,7 +582,9 @@
 		eval command=\${jail_${_jv}_program:-$jail_program}
 		echo -n " ${_hostname:-${_j}}"
 		_tmp=`mktemp -t jail` || exit 3
-		$command -q -f $_conf -r $_j >> $_tmp 2>&1
+		cat $_conf $jail_conf $jail_conf_dir/*.conf \
+		/etc/jail.*.conf 2>/dev/null | \
+		$command -q -f - -r $_j >> $_tmp 2>&1
 		if $jail_jls -j $_j > /dev/null 2>&1; then
 			cat $_tmp
 		else