Hi, I am just going through Conway's game of life to understand how this works. I am using the Eclipse plug-in to make life easier. I see you can either use the agenda-group style, or the rule-flow style. Some points of confusion: 1. In killAll.rf, there is "calculate before" and "calculate after", and they both use ruleFlowGroup="calculate"... Are ruleFlowGroups set in the XML? (ie. the UI doesn't allow you to edit this) 2. In generation.rf, there is a splitter and joiner around 'kill' and 'birth'. However, in the AgendaGroupDelegate.nextGeneration() code, the agenda groups are 'stacked', such that 'birth' rules will be executed before 'kill' rules. Is there any real difference here? Thanks, -- View this message in context: http://www.nabble.com/Help-understanding-rule-flow-tp26023797p26023797.html Sent from the drools - user mailing list archive at Nabble.com.