Sustainability certification systems play both an agenda-setting and practical role for a variety of architecture, planning, and engineering project types. The evolution of existing systems and the creation of new certification systems to address a broader set of social sustainability topics provide a unique opportunity to explore the different ways the industry is thinking about and applying social equity ideas to varied projects. We explore this diversity by conducting a content analysis of the guidance documents from eight sustainability certification systems to better understand how social equity is defined, the context in which the concept is applied, and how systems value the idea. The manner and degree to which systems engage with recognitional, procedural, and distributional aspects of social equity varies. Consequently, there is no guarantee that certification leads to real-world equitable outcomes. Moreover, sustainability professionals seeking to use certification systems to address unequal social impacts or benefits still need to bring a clear set of goals regarding equity of what and for whom, as well as ideas of how to measure and evaluate the distribution of social costs/benefits in order to put social equity into practice.