To use 3PLs to track warehouse performance metrics, you need to define your goals and objectives, negotiate your service level agreements (SLAs), implement data integration and analysis tools, and review and improve your performance. You should consider the key performance indicators (KPIs) that matter most to you and your customers, the specific services and standards that your 3PLs will provide, the systems and platforms that you and your 3PLs will use to exchange and analyze data, how often you will evaluate and compare your performance with your 3PLs and industry benchmarks, and how you will identify gaps and opportunities for improvement. Additionally, you must ensure data quality, security, and compatibility, generate and visualize reports and dashboards, handle issues and disputes, set penalties or incentives for performance, implement action plans, track best practices, and more.