The Department of Community Development administered the City's comprehensive plan and provided direction and support for the City's physical and economic development through community planning. DCD was established in 1969 and assumed the responsibilities of the City Planning Commission and the Urban Renewal Program. In 1972, the Office of Economic Development was created in the Department to provide information to businesses that were expanding or relocating in Seattle. DCD was the lead agency for implementing various types of grant funded projects, such as the Neighborhood Improvement Program, Targeted Neighborhood Assistance Program, and Neighborhood Development Program. DCD was abolished in 1992 and its programs were relocated in the Department of Neighborhoods, Department of Housing and Human Services, Planning Department, and other agencies. DCD records include material from the City Planning Commission, Zoning Commission, Metropolitan Arts Commission, Board of Adjustment, and Urban Renewal Program.

The City Planning Commission was created in 1924 to prepare plans and gather data for the development of the City, to advise City Council on current problems and long range planning, and to participate in administration of the City's Zoning Ordinance. An independent nine-member commission was established with adoption of a new City Charter in 1946. It was provided with authority to hire as needed to carry out its planning and advisory functions. The Planning Commission also administered the Board of Adjustment following its creation in 1957.

The city planning process was reorganized in 1980 and the Commission's planning function was transferred to the Department of Community Development. The current Commission is an advisory agency that reviews development plans and reports to the Mayor and City Council. It is composed of 15 members, all of whom must be Seattle citizens.

In 1959, a City ordinance designated the area "bounded by Yesler Way, Empire Way South, Lake Way, Rainier Avenue South, and 14th Avenue South" a "blighted area" and proposed an urban renewal project -- the 340-acre Yesler-Atlantic Neighborhood Improvement Project -- which would fund "rehabilitation, redevelopment, or a combination thereof" with federal dollars. The City was authorized to apply for $89,200 to fund plans and surveys of the area; this figure was later amended to $137,854. A $2 million capital grant was requested to demolish decaying structures and construct and install "streets, utilities, parks, playgrounds...public buildings or facilities..."; displaced families would be relocated.

In 1959, when the federal government expressed concern about the costs of funding the entire project, the area to be improved was divided into two sections (the Yesler-Atlantic "U" and the "T," so named for the shape of the areas covered). The 137-acre "T" was selected as the first to undergo development because a large non-cash grant would accrue from the construction of the New Washington Junior High School in the "T" area. Survey and planning of the area began in 1960.

In 1966, a new plan for the Yesler-Atlantic neighborhood was approved; structural inspections and an economic feasibility study were carried out, and a new project plan was created. A public hearing was scheduled for discussion of the new plan, and some property owners petitioned to have the hearing delayed on the grounds that the City Council had not made known the special procedures that applied to urban renewal hearings. Although their request was denied, the resulting litigation would delay the start of the project until 1968. In 1968, the project received HUD approval. By 1973, 42 homes had been rehabilitated, new complexes had been constructed, and a new park had been completed.