Government budget crises have compelled state Extension Services to defend their receipt of state and county funding. A key to that defense is persuading citizens and policymakers of Extension's "public value": the benefit from Extension programs to those who are not directly served. This paper uses the principles of public sector economics to help formulate that defense and describes how Extension staff have applied economic principles to identify the public value in their own programs. The approach, developed into a workshop for program teams, serves to both sustain programs that have strong public value and identify programs that do not.