This document discusses the history and principles of mixed land use development. It begins by defining mixed land use as any combination of residential, commercial, and industrial uses that are physically and functionally integrated. The document then outlines the history of mixed land use, noting that traditional settlements were typically mixed use but industrialization led to more separated uses. It describes how modern zoning laws further separated uses but that mixed use is now seen as beneficial for compact development, pedestrian environments, and strong communities.