A fluid delivery system that includes an infusion pump and a cassette (1) with tubing (75) that is configured for engaging the pump mechanism of the infusion pump to accurately and repeatably deliver a fluid to a subject. The cassette has a housing with first and second ends for holding flexible tubing through which the fluid is directed, and the tubing engages a pumping mechanism to provide movement of the fluid through the tubing. When engaged with the pumping mechanism, the length of tubing is accurately and repeatably positioned in contact with and between the curved wall and the pumping mechanism.