After years when the relationship between the city and industry was characterized by an ongoing process of cities rejecting and removing industry, a paradigm shift is discernable, both due to increasing awareness of the importance of industry for the city. A prominent planning trend related to this reversal is the creation of mixed-use environments that house a range of activities, both throughout the city and in industrial zones. This trend contributed to the formation of a new structural typology in which residential and industrial/employment uses coexist. This document conceptualizes this arrangement as “synchronous typology.” Using our mapping and analysis of varied projects from around the world as the foundation, we developed a preliminary conceptual index of synchronous typologies, focused on the architectural and urban scales. We further outline principles for the optimal integration of the various synchronous typologies in urban environments, according to their distinct characteristics.