The Immigration Reform and Control Act of 1986 (IRCA) provides for the legalization of undocumented aliens through several programs. IRCA established the State Legalization Impact Assistance Grants (SLIAG) "to alleviate the financial impact on States and local governments that may result from the adjustment of immigrant status" through the legalization program. Under SLIAG $1 billion per year during the four fiscal years beginning in 1988 will be made available for states for the following types of social services: (1) public assistance; (2) public health assistance; and (3) education. Planning for the SLIAG program at the state and local levels has been very difficult because of a lack of information about the newly legalized population; this survey provides a broad profile of that population, assessing its service usage, and likely service needs. More than 100 people who have worked closely with the aliens in seven states were surveyed. Information is given on the following: (1) size of population (as of March 24, 1988, there were 1,258,359 applications for legalization); (2) nationality; (3) distribution within states; (4) demographic characteristics, including sex, age, marital status, education and language skills, health status and service needs, employment status, income, potential public assistance utilization, housing status, and geographic mobility. Recommendations are made in the following areas: (1) general; (2) health; (3) education; and (4) employment, income, and public assistance. Data are presented on eight tables. (BJV)