Hi, Consider a scenario where multiple threads continuously assert facts using StatefulSession.insert() method. public class RulesManager { private RuleBase ruleBase; private StatefulSession session; public RulesManager() { ruleBase = RuleBaseFactory.newRuleBase(); session = ruleBase.newStatefulSession(); } public void fireRules(Object fact) { session.insert(fact); session.fireAllRules(); } } In this scenario, do we need to synchronize StatefulSession for thread safety? -- View this message in context: http://www.nabble.com/Synchronizing-StatefulSession-tp19740667p19740667.html Sent from the drools - user mailing list archive at Nabble.com.