Since the late 2000s, interest in the development and use of shared measures in the informal science, technology, engineering, and mathematics (STEM) education (ISE) field has increased. The intent is to build the capacity of evaluators to measure common outcomes of ISE experiences. We begin this chapter with a definition of shared measures, a description of related technical qualities of these measures, and a discussion of benefits and concerns around the use of shared measures. We then review recent conversations and developments around shared measures, including examples of observational