Routing is based on rules. The rules allow you to vary which workflows initiate based on information passed to the workflows from the initiating event. You can attach rules to events that initiate workflows. When multiple rules are tied to the same event, the rule with the highest rank is used. The event and rank determine which rules are applicable. In the case of an equal event and rank, all rules are valid and are used. You can use attribute filters to narrow down the scope of the rule. If you do not define any filter for the rule, then there is no narrowing, and Orchestration assigns the rule only based on event and rank.