A service level agreement (SLA) is a contract that defines the quality and volume of specific deliverables and service level requirements for both parties involved. A comprehensive SLA will include performance metrics to ensure that the expectations of both parties are being met throughout the outsourcing engagement. An SLA is a subordinate agreement to a master services agreement (MSA). An SLA is created during the contracting stage of the training outsourcing process. Other agreements include purchasing agreements, purchase orders and statements of work.