The following DRL produces a Null Pointer Exception when the "enabled" attribute is set to false on "test rule 2". Any ideas why? Changing this value to true or commenting out the rule causes things to succeed. Environment: Java 7 and Drools 5.4 package tests import org.apache.log4j.Logger; import java.util.List; global Logger log declare Data name : String end rule "insert Data" when then insert(new Data("test")); end rule "test rule 2" enabled false when d : List() from collect (Data( name == "test") ) then log.info(String.format("%s hit on %s", kcontext.getRule().getName(), d)); end Exception executing consequence for rule "insert Data" in tests: java.lang.NullPointerException at org.drools.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39) at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1283) at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1209) at org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1442) at org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:710) at org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:674) at org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:230) at org.drools.impl.StatelessKnowledgeSessionImpl.execute(StatelessKnowledgeSessionImpl.java:278) at tests.DroolsTest.testStateless(DroolsTest.java:98) at tests.DroolsTest.runTest(DroolsTest.java:60) at tests.DroolsTest.main(DroolsTest.java:45) Caused by: java.lang.NullPointerException at org.drools.common.DefaultAgenda.createActivation(DefaultAgenda.java:569) at org.drools.reteoo.RuleTerminalNode.modifyLeftTuple(RuleTerminalNode.java:297) at org.drools.reteoo.SingleLeftTupleSinkAdapter.propagateModifyChildLeftTuple(SingleLeftTupleSinkAdapter.java:259) at org.drools.reteoo.AccumulateNode.evaluateResultConstraints(AccumulateNode.java:676) at org.drools.reteoo.ReteooWorkingMemory$EvaluateResultConstraints.execute(ReteooWorkingMemory.java:591) at org.drools.common.PropagationContextImpl.evaluateActionQueue(PropagationContextImpl.java:345) at org.drools.common.NamedEntryPoint.insert(NamedEntryPoint.java:342) at org.drools.common.NamedEntryPoint.insert(NamedEntryPoint.java:298) at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:888) at org.drools.base.DefaultKnowledgeHelper.insert(DefaultKnowledgeHelper.java:187) at org.drools.base.DefaultKnowledgeHelper.insert(DefaultKnowledgeHelper.java:181) at tests.Rule_insert_Data_2eb7a40b15e640d6bc777e1075d1218b.defaultConsequence(Rule_insert_Data_2eb7a40b15e640d6bc777e1075d1218b.java:7) at tests.Rule_insert_Data_2eb7a40b15e640d6bc777e1075d1218bDefaultConsequenceInvokerGenerated.evaluate(Unknown Source) at tests.Rule_insert_Data_2eb7a40b15e640d6bc777e1075d1218bDefaultConsequenceInvoker.evaluate(Unknown Source) at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1273) -- View this message in context: http://drools.46999.n3.nabble.com/Bug-in-enabled-rule-attribute-tp4019049... Sent from the Drools: User forum mailing list archive at Nabble.com.