Organizations today face mounting pressure to demonstrate robust data privacy and security practices, particularly when working with third-party vendors and service providers. This comprehensive guide explores how data privacy and third-party risk management (TPRM) teams can work collaboratively to create a unified approach that safeguards sensitive customer data across all external relationships. With the evolving regulatory landscape, including multiple US state privacy laws and the aftermath of Schrems II, companies must implement integrated strategies that encompass data mapping, transfer impact assessments, and centralized third-party inventories. The guide provides 10 essential best practices for achieving privacy compliance when working with third parties, emphasizing the importance of understanding data flows, assessing fourth and fifth-party risks, and maintaining comprehensive oversight of all vendor relationships.