A delivery system for delivering fluidic media may include a second housing configured to be selectively operatively engaged with and disengaged from a first housing portion adapted to be carried by a user. One of the housing portions may support a reservoir for containing fluidic media and a plunger head moveable within the reservoir. A drive device may be supported by the other of the housing portions for coupling with the reservoir upon the housing portions being operatively engaged. A first interactive element may be supported on the first housing portion for interacting with a second interactive element supported on the second housing portion. Circuitry may be configured to detect an interaction between the interactive elements and configured to provide a signal or a change in state in response to the housing portions being operatively engaged and an interaction between the interactive elements being detected.