Power and control systems for a drug delivery device allow for the activation, control of, and communication with the drug delivery device. The power and control system allows for a delay between device activation, and optionally needle insertion, and commencing drug delivery. The delay may be for a predetermined time. In addition, the power and control system may communicate with one or more external sensors and devices. The inputs from the sensors and devices may automatically, or on demand, adjust the delivery parameters of the device. The power and control systems may control a drive system that delivers a fluid at a variable rate or profile, allowing for the delivery to be tailored to maximize the effectiveness of the treatment.
