Effective source water protection often requires the collaboration of multiple stakeholders to implement strategies that address the issues facing the resource. Engagement with multiple partners fosters opportunities to pool resources, build commitment, and support communal planning actions that address diverse threats and ensure sustainable clean drinking water. This presentation describes ongoing work at Willisburg Lake Reservoir (Willisburg, KY) and explores how efforts to address source water protection have grown into a regional collaborative effort to protect the watershed as a whole.