This study examines the relationship between income and housing assistance programs. The welfare system, through the explicit and implicit shelter allowances that welfare recipients receive as part of their public assistance benefits, spends at least $10 billion a year on housing assistance. The Department of Housing and Urban Development spends a similar amount. Yet, the two streams of government financing for low income housing are uncoordinated and frequently overlapping. Part 1 presents new evidence on both the nature and the impact of this two-pronged approach to providing shelter assistance to the poor. It compares the level of benefits available to households receiving various combinations of aid, and documents the housing outcomes that are produced by the two systems of shelter support. It includes the following chapters: (1) Executive Summary; (2) Introduction; (3) Shelter Allowances Under the Welfare System; (4) The Impact of the Two-Pronged System; and (5) Directions for Future Policy. Part 2 presents detailed statistics on estimated shelter allowances for each of the 50 states and the District of Columbia under the following programs: (1) Aid to Families with Dependent Children (AFDC); (2) Supplemental Security Income (SSI); and (3) General Assistance (GA). Extensive statistical data are included on 42 tables, two graphs, and six appendices. (FMW)