Techniques for detecting and resolving feature interactions during calls are disclosed. In particular, a finite-state machine and a corresponding method detect when a feature that is invoked during a call would interact with another previously-activated feature, and ensure that both features are not active simultaneously. Three different techniques for resolution are disclosed: in one technique, activation of the latter feature is always refused; in a second technique, the former feature is always deactivated and the latter feature is then activated; and in a third technique, one of the two features is selected to be the active feature—perhaps based on priorities assigned to the features—and the features are activated and/or deactivated accordingly.