A delivery device includes a durable housing portion and a separable disposable portion that selectively engage and disengage from each other. The disposable housing portion secures to the patient and may be disposed of after it has been in use for a prescribed period. Components that normally come into contact with a patient or with infusion media are supported by the disposable housing portion for disposal after the prescribed use, while the durable housing portion supports electronics for controlling delivery of infusion media from the reservoir and a drive device and drive linkage.