I believe this is an example of backwards-chaining. (From the manual) Drools only supports forward-chaining at present although "...Drools will be adding support for Backward Chaining in its next major release...". Have you looked at Geoffrey De Smet's drools-solver excellent work? Will this provide what you need? Cheers, Mike _____ From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Ravi Shankar (Singtel) Sent: 22 April 2008 23:25 To: rules-users(a)lists.jboss.org Subject: [rules-users] What-if analysis Dear all, Does Drools support "what-if" analysis? For example, I have the data for the sales done by a salesman for the past one year. There is a commission available to the salesman for the same he is doing. I use the data to plot a graph showing the efficiency of all salesmen in my company. Assume that the comany wants a profit of , say, 10% more than what currently is, I mean "what if the comany wants more revenue", what should be the values for sales. It is a trivial example, but just enough for understanding my query - can we use Drools for this? Is it being used in financial inductry where derivatives etc are used widely? Thanks and regards, Ravion