Abstract: The present invention is an interface system for interactively building rules and constraints. The interface system comprises of an output display configured to show a user a partial complete rule with a current rule fragment, such rule fragment comprising a blank space. The user can fill in the blank space by either choosing from a list or by typing in text in the blank space. After the blank space is filled, a completed rule is generated. The interface system then assigns this rule to one or more person in a resource scheduling system. The present invention can be used for agent scheduling in a call center environment.