A wearable infusion device comprises a reservoir (222) that holds a liquid medicament, an outlet port (250) that delivers the liquid medicament to a patient and a pump (224) that holds a volume of the liquid medicament received from the reservoir and displaces substantially all of the volume of the liquid medicament when actuated. A first valve (232) is between the reservoir and the pump and a second valve (234) is between the outlet and the pump. The device includes a first actuator (216) that, when activated, closes the first valve and opens the second valve, a second actuator (218) that, when activated, actuates the pump, and a linkage (254) that precludes the second actuator from being activated until the first actuator is activated.
