Metering systems and methods are disclosed. A metering system is part of a larger fluidics sub-system that includes a flexible reservoir for storing insulin and a cannula assembly for delivering the insulin into sub-cutaneous tissue. The metering system draws a small dose of fluid from the reservoir and then pushes it down the cannula line and into the patient. The fluid dose is small relative to the reservoir volume, such that many pump strokes are required to completely empty the reservoir.