Book excerpt: By 2025, two thirds of the world’s population will be living in water stressed conditions. Meanwhile, the degradation of water ecosystems is occurring at alarming rates. Water utilities and water regulators that choose to play an active role in catchment management with nature based solutions (NBS) are uniquely positioned to help. Building a robust knowledge base and supporting opportunities for cross-sector collaboration are fundamental to the mainstreaming of NBS. The International Water Association (IWA) and The Nature Conservancy (TNC) are working together to encourage and facilitate active utility involvement in NBS, as well as promoting stronger connections between water utilities and regulatory bodies. Implementation of NBS involves multiple, interdependent stakeholders at various governance levels, and consequently regulators a key role in creating the enabling environments for these interactions and negotiations. This publication taps into diverse geographies and contexts, delving into case studies for a richer conversation that addresses the variety of challenges and elements for success for integrating NBS into water utility operations and planning. By publicizing successful case studies, the IWA/TNC partnership fulfils a dual purpose of endorsing these efforts and providing actionable guidance for other water utilities striving to improve their sustainability and resiliency.