Less than two decades after Sears, Roebuck-once the nation's largest mail-order business-entered the retailing business in 1924, it had gained prominence in that field nearly equal to that of its competitors. This unprecedented rate of expansion was marked by innovations in merchandising and store design. Sears was a pioneer in creating department stores that catered to men as well as women, that eschewed style in favor of practicality in merchandise, and that allowed customers to select goods without the aid of a clerk. The buildings likewise broke from convention. They were generally oriented to motorists-set apart from existing business districts amid residential areas occupied by their target audience; had ample, free, off-street parking; and communicated a clear corporate identity. In the 1930s, the company designed fully air-conditioned, "windowless" stores whose layout was driven wholly by merchandising concerns. In all these respects, Sears set important precedents that were widely followed by other major retailers after World War II.

The 1920s and 1930s were crucial decades in laying the groundwork for the shopping center as a major force in retail development during the second half of the twentieth century. The concept of the shopping center as a fully integrated business enterprise became significantly more sophisticated and ambitious. Sizable complexes were initiated that included at least several dozen businesses purveying not only routine goods and services, but a variety of more specialized ones as well. Thus cast, the shopping center became more than a place of convenience; it formed a destination-a focus of activity and a physical landmark in the fast-growing suburban landscape. Despite their pivotal role, these large community shopping centers remained few in number during the initial decades of their development. The projects that were undertaken were experimental, and hence tentative in nature. They were also highly individualistic in appearance and other physical characteristics, reflecting the vision and the taste of the developers who created them. Many were integral parts of comprehensively planned residential communities and were conceived as much to control and contain commerce as to foster it. In such ways, this first generation of large shopping centers offer conspicuous contrast with their post-World War II offspring. Their influence on later work was nonetheless crucial, for they demonstrated the advantages of meticulous planning and management in the fiercely competitive area.

During the 1930s the neighborhood shopping center emerged as an important phenomenon in the development of retail facilities in the United States. Prior to that decade, the type was limited to a modest number of examples built as components of planned residential subdivisions for the well-to-do. By the eve of World War II, the neighborhood shopping center was seen as an advantageous means of meeting the routine needs of people in outlying urban areas generally. During the 1930s, the neighborhood center also became one of the first common building forms to experience a basic reconfiguration to accommodate patterns of widespread automobile usage. Washington, D. C., was the initial and by far the most intensive proving ground for this work at its formative stage. The results were influential nationwide in the shopping center's transformation from a novelty to a ubiquitous feature of the American landscape.