William Kenneth Brussat, 56, a specialist in intergovernmental relations at the Office of Management and Budget, died of cancer Sunday at Doctors Hospital.

Mr. Brussat worked for the Chicago Redevelopment Agency before moving to the Washington area in 1955 to work with the Webb & Knapp real estate firm on the redevelopment of Southwest Washington. From 1959 to 1960, he was a special assistant in the White House for public works planning and then spent a year with the Urban Renewal Administration.

He joined the Bureau of the Budget, now OMB, in 1963 after spending a year as a private consultant.

Mr. Brussat was a management analyst at OMB. He developed programs for closer cooperation of governments at the municipal, county, state and federal levels. He received OMB's Exceptional Service Award this year and remained active in the agency until his death.

Mr. Brussat was born in Milwaukee, Wis. He served in the Army in Europe during World War II. He later took bachelor's and master's degrees at the University of Wisconsin and then studied at the School of Civic Design in Liverpool, England, as a Fulbright scholar.

Survivors include his wife, Mona, of the home in Washington; three sons, David, of Washington, Guy, of Skykomish, Wash., and Tony, of the home; a sister, Gloria Bartels, of Inverness, Fla., and three brothers, Lee, of Milwaukee, Carroll, of Greenfield, Wis., and Bob, of Wild Rose, Wis.

The family suggests that expressions of sympathy be in the form of contributions to Children's Hospital.