Apparatuses and methods for a connection interface between a reservoir or syringe, infusion set tubing, and an infusion pump are provided. A base is provided which is adapted to receive a reservoir and engage a cap. A piercing member, such as a needle, is disposed in the interior of the cap in such a manner that the needle is separated from the reservoir septum when the base is in a first detent position, and the needle pierces a reservoir septum when the base is in a second detent position. When the reservoir, the base and the cap are connected to form an integrated unit, this unit is then capable of being inserted and secured in the infusion pump housing. In some embodiments, an integral connector couples directly to the reservoir.