Federal statistical services grossly underestimate the size of the farmworker population; as a result, the current federal farmworker programs (CETA, Migrant Education, Migrant Headstart, Farm Labor Housing, and Migrant Health) are unable to identify a total target population in need of services and unable to allocate funds in ways which reflect the actual needs of the migrant and seasonal farmworker (MSFW) population. Population underestimation is directly attributable to the use of arbitrary and restrictive definitions of "farmwork,""seasonality," and "migrancy" and to the practice of counting the jobs available for hired agriculture labor rather than the agricultural laborers. A new model, constructed by refining and combining data currently used by the federal farmworker programs, produces estimates of the farmworker population 34% higher than the highest federal statistical services estimate and more than 6 times higher than the lowest estimate. The federal government should produce uniform standards for defining the MFSW population, gather demographic and socio-economic data for the population, and attempt to identify all eligible farmworkers and their families. (JH)