This document outlines three main theories of retail development: environmental, cyclical, and conflictual. The environmental theory states that retailers must adapt to changes in their operating environment like technology, the economy, and demographics in order to survive. The cyclical theory includes the wheel of retailing and accordion theory, which propose that retailers go through different phases or change formats over time. Finally, the conflict theory suggests that new retail formats emerge through a dialectic process as different types of retailers compete with each other and eventually blend to create innovative new formats.