William L. Slayton, 82, an urban renewal pioneer who was a key player in the redevelopment of Southwest Washington and who went on to direct the federal agency charged with renewing American cities, died Aug. 7 at Georgetown University Hospital. He had suffered a stroke.

Mr. Slayton was commissioner of the Urban Renewal Administration in the Housing and Home Finance Agency under presidents Kennedy and Johnson, up until the creation of the Department of Housing and Urban Development.

Regarded as one of the early academic thinkers in the field of modern urban renewal, he had been a vice president for planning and redevelopment in Washington for Webb and Knapp.

It was the wide-ranging real estate firm headed by William Zeckendorf of New York and was a primary builder in the renewed Southwest.

Mr. Slayton was also the planning partner in the architectural firm of I.M. Pei, whose redevelopment projects included Society Hill in Philadelphia and Hyde Park-Kenwood in Chicago as well as Southwest in the District.

The lessons of Southwest's renewal in the 1950s and early 1960s were hard taught, resulting in the scattering of hundreds of low-income families around the city without careful regard to their fate.

After he took over the federal program, Mr. Slayton instituted regulations requiring redevelopment agencies to ensure that adequate relocation housing was available.

He also implemented rules to combat racial discrimination in relocation housing and to stiffen building enforcement codes in urban renewal agencies.

After HUD was formed and he left federal office in 1966, Mr. Slayton was executive vice president of Urban American, creator of the National Urban Coalition.

He was also executive vice president of the American Institute of Architects, and oversaw creation of its headquarters on New York Avenue NW.

He was deputy assistant secretary of state in charge of the office of foreign buildings at the end of his career, with responsibility for design and construction of embassies and other federal facilities abroad.

During his tenure, chanceries were built in Cairo, Lisbon, Kuala Lumpur, Sri Lanka, Moscow and elsewhere. He retired in 1983.

Mr. Slayton was born in Topeka, Kan., and grew up in Omaha, where he attended the University of Omaha.

He was a graduate of the University of Chicago, where he also received a master's degree in public administration.

As a graduate student, he was an economic research assistant to professor Paul H. Douglas, later Democratic senator from Illinois. Mr. Slayton was Douglas's political secretary when he was a Chicago alderman and was treasurer of Douglas's Senate primary race in 1942.

After that, Mr. Slayton was a planning analyst and special assistant to the mayor and city council in Milwaukee. He served in the Navy during World War II. He helped produce a two-volume seminal work on urban redevelopment for the University of Chicago.

His first job in Washington was as a field representative for the Housing and Home Finance Agency. He was the associate director for redevelopment for the National Association of Housing Officials before joining Webb and Knapp.

Mr. Slayton, who had served on the school board in Park Forest, Ill., was chairman of the Montgomery County Citizens Planning Committee, and ran unsuccessfully for Montgomery County Council in 1952.

He later moved from Kensington to Ordway Street NW, into a triple-arched house designed by Pei. It is one of only two Pei houses in the city.

Mr. Slayton was treasurer of the Potomac Institute, chairman of the National Housing Research Council and a member of the boards of the Washington Planning and Housing Association, National Housing Conference and Arena Stage.

He belonged to a number of other planning organizations. His honors included the highest award of the National Association of Housing and Redevelopment Officials.

Mr. Slayton, whose suffered from macular degeneration in his later years, was a director of the Washington Ear, which provides recordings to the visually impaired.

Survivors include his wife of 58 years, Mary Louise Prichard Slayton of Washington; two daughters, Mary Elizabeth Slayton Campbell of Salt Lake City and Barbara Jean Slayton Shelton of East Quoque, N.Y.; a brother, Clarence H. Slayton Jr. of Mount Airy; and four grandchildren.