Rookie error -- I neglected to put the modify() in the RHS of a rule. That'll make a big difference. :-) -- View this message in context: http://drools.46999.n3.nabble.com/Planner-IntConstraintOccurrence-not-being-retracted-tp4018672p4018710.html Sent from the Drools: User forum mailing list archive at Nabble.com.