I answered a performance question a user had about drools-solver, but I'm afraid I answered with a touch of ignorance about the way drools-solver is set up. His rules had a new object being inserted into the working memory each time a constraint rule was matched. The constraint objects were then accumulated by a low priority rule at the end. After looking at the drools-solver examples it looks like they're all that way. It strikes me that having a single accumulator object, and not creating and inserting a new object in each constraint rule, would be more efficient. Is it possible to set this up in a solver ruleset? Thanks, GreG