diff --git a/configure.ac b/configure.ac
index 094da52..25012d5 100755
--- a/configure.ac
+++ b/configure.ac
@@ -82,6 +82,8 @@
 [  --disable-ospfd         do not build ospfd])
 AC_ARG_ENABLE(ospf6d,
 [  --disable-ospf6d        do not build ospf6d])
+AC_ARG_ENABLE(isisd,
+[  --disable-isisd         do not build isisd])
 AC_ARG_ENABLE(bgp-announce,
 [  --disable-bgp-announce, turn off BGP route announcement])
 AC_ARG_ENABLE(netlink,
@@ -702,6 +704,12 @@
   *    ) ;;
 esac
 
+case "${enable_isisd}" in
+  "yes") ISISD="isisd";;
+  "no" ) ISISD="";;
+  *    ) ISISD="isisd";;
+esac
+
 if test "${enable_bgp_announce}" = "no";then
   AC_DEFINE(DISABLE_BGP_ANNOUNCE,,Disable BGP installation to zebra)
 fi
@@ -712,6 +720,7 @@
 AC_SUBST(RIPNGD)
 AC_SUBST(OSPFD)
 AC_SUBST(OSPF6D)
+AC_SUBST(ISISD)
 AC_SUBST(VTYSH)
 AC_SUBST(INCLUDES)
 AC_SUBST(CURSES)
@@ -1034,6 +1043,7 @@
 AC_DEFINE_UNQUOTED(PATH_BGPD_PID, "$quagga_statedir/bgpd.pid",bgpd PID)
 AC_DEFINE_UNQUOTED(PATH_OSPFD_PID, "$quagga_statedir/ospfd.pid",ospfd PID)
 AC_DEFINE_UNQUOTED(PATH_OSPF6D_PID, "$quagga_statedir/ospf6d.pid",ospf6d PID)
+AC_DEFINE_UNQUOTED(PATH_ISISD_PID, "$quagga_statedir/isisd.pid",isisd PID)
 AC_DEFINE_UNQUOTED(ZEBRA_SERV_PATH, "$quagga_statedir/zserv.api",zebra api socket)
 AC_DEFINE_UNQUOTED(ZEBRA_VTYSH_PATH, "$quagga_statedir/zebra.vty",zebra vty socket)
 AC_DEFINE_UNQUOTED(RIP_VTYSH_PATH, "$quagga_statedir/ripd.vty",rip vty socket)
@@ -1041,6 +1051,7 @@
 AC_DEFINE_UNQUOTED(BGP_VTYSH_PATH, "$quagga_statedir/bgpd.vty",bgpd vty socket)
 AC_DEFINE_UNQUOTED(OSPF_VTYSH_PATH, "$quagga_statedir/ospfd.vty",ospfd vty socket)
 AC_DEFINE_UNQUOTED(OSPF6_VTYSH_PATH, "$quagga_statedir/ospf6d.vty",ospf6d vty socket)
+AC_DEFINE_UNQUOTED(ISIS_VTYSH_PATH, "$quagga_statedir/isisd.vty",isisd vty socket)
 
 dnl ---------------------------
 dnl Check htonl works correctly
@@ -1063,7 +1074,7 @@
 
 AC_OUTPUT(Makefile lib/Makefile zebra/Makefile ripd/Makefile 
 	  ripngd/Makefile bgpd/Makefile ospfd/Makefile 
-	  ospf6d/Makefile vtysh/Makefile doc/Makefile 
+	  ospf6d/Makefile isisd/Makefile vtysh/Makefile doc/Makefile 
 	  ospfclient/Makefile
 	  redhat/quagga.spec
 	  lib/version.h)