Headwater streams are diverse ecosystems and important sources of water and dissolved and particulate resources to the downstream river network. However, across the world, they are rapidly being degraded or lost through human activities, particularly urban development. This degradation and loss have negative consequences for the structure and function of headwater streams, as well as downstream river networks. Despite long-held recognition of the ecological value of headwater streams and the impacts of their widespread loss, there remains a large gap between developing strategies and tangible action. To address this gap, we, a group of cross-disciplinary researchers and practitioners from multiple organizations and locations, developed a framework to guide strategic decision-making and a comprehensive set of structural and nonstructural tools that can be used to protect headwater streams in urbanizing areas where opportunities to protect waterway health are being considered by local waterway practitioners and the community. The framework was tested by applying it to 4 contrasting case studies of urbanization with different physiographic, policy, and legislative settings. Our evaluation showed that the framework provides a useful generic mechanism that can be used by policymakers, planners, and other stakeholders to diagnose the status of headwater stream protection in a variety of urban areas and to support structured stakeholder conversations about what is desirable, practical, and achievable for their context.