An analysis ofpubliclyfundedfamilyplanning services in Iowa was undertaken to provide tangible estimates based on local data of the value of these services in averting unplanned and unwanted births to women who voluntarily use them. The study reports methods that can be applied by other states in evaluating their own family planning programs. Benefits were measured as the cost savings in public expenditures avoided by providing family planning services to lowand marginal-income women. Iowa data for AFDC, food stamps, and Medicaid payments were used to calculate benefits. The total benefit savings were adjusted to reflect the impact of family planning services on preventing births. The adjusted savings were accrued over one-year and five-year time frames and for four age groups (14-19, 20-29, 30-34, and 35-44). lin the base year, the cost of providing family planning services in Iowa to the more than 56,000 women who used them was $3.1 million, or $59 per user. Results showed that the benefits of family planning services were highest for teenagers who would become eligible for public assistance programs upon the birth of a child.