With kind regards, Geoffrey De Smet Op 10-08-10 09:03, Joshua Daniel schreef: when - there is a course for a curriculum for a room - and there is a course with a higher id for the same curriculum for a different room then insertLogical ... take a look at the other constraints for the actual implementation, but it pretty much writes itself :) Seperate course (of the template week) from courseInstance (a course in a specific week). Generate all the timeslots and courseInstance of a year (instead of all those of a week) and insert those too. Your number of possible solutions will explode (which is ok), to deal with that you 'll have to mix in big moves to get good results, such as a move which moves all the courseInstances of a single course (so the courseInstances in all different weeks) to another timeslot (in the same week of the coureInstance) No idea :) 5.1 is out, drools solver has been renamed to drools planner. Use 5.1 :) See the UpgradingFromPreviousVersionRecipe.txt in the zip download.