I'm not sure you can nest rules, you are thinking too procedural, but you can extend conditions/lhs from other rules. Here is an example from the test case in the drools source "extend_rule_test.drl" that may help you. rule "test rule 1" enabled false when c: Cheese( type == "stilton" ) then list.add( new String ("rule 1") ); end rule "test rule 2" extends "test rule 1" enabled false when Cheese( price <= 6.00) from c then list.add( new String ("rule 2") ); end rule "test rule 3" extends "test rule 2" when Cheese( price > 1.00 ) from c then list.add( new String ("rule 3") ); end Rule 1 & 2 are disabled, but rule 3 in the rete network will have all 3 LHS (conditions). So the above would render. rule "test rule 3" when c: Cheese( type == "stilton" ) Cheese( price <= 6.00) from c Cheese( price > 1.00 ) from c then list.add( new String ("rule 3") ); end This was modeled more after how a programming language would have one class extend another, but it only inherits the LHS. -Michael P.S. I believe this is available only in trunk at this time, but will be out with the next 5.x release. From: rules-dev-bounces(a)lists.jboss.org [mailto:rules-dev-bounces@lists.jboss.org] On Behalf Of David Sinclair Sent: Wednesday, November 12, 2008 8:50 AM To: m_dilipkumar2006(a)yahoo.co.in; Rules Dev List Subject: Re: [rules-dev] Regarding Nested Rules in Drools 4.0.7 I think u are thinking about this in the wrong sense. You don't want to call another rule. You can assert a fact that will cause that other rule to fire. On Wed, Nov 12, 2008 at 9:45 AM, M.DILIP KUMAR <m_dilipkumar2006(a)yahoo.co.in&gt; wrote: Hi All, I got many idea by using this group. Now i want one clarification regarding Nested rule. If any one having sample code for nested Rule means Pls send reply along this mail. Acutally i want rule like Rule : "nested Rule" When #Condition is true Then CALL another RULE ...!!!! Here i want pass some argument to that nested rule is it possible ? End Help me regarding this and send sample code if possible please Defeat yourself today! ____________________________ Error! Filename not specified.DILIP KUMAR.M _____ Add more friends to your messenger and enjoy! Invite them now. <http://in.rd.yahoo.com/tagline_messenger_6/*http:/messenger.yahoo.com/inv ite/> _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev