A Service Level Agreement (SLA) is a formal document that outlines the expectations and responsibilities between a service provider and a client. It specifies the quality and type of service that the provider must deliver, including response times, availability, and performance metrics. This agreement helps ensure that both parties have a clear understanding of what is expected, which can lead to better communication and satisfaction. SLAs are commonly used in various industries, such as IT services, telecommunications, and customer support. By setting measurable goals, SLAs help clients hold providers accountable and provide a framework for resolving issues if the agreed-upon standards are not met.