Representation theory (RT) is one of few long-standing, native theories in the Information Systems discipline. Over the past 30 years, RT has spawned a wide program of research, primarily on modeling of information systems but also on other phenomena such as data quality, system alignment, security, and effective system use. Nonetheless, descriptions of RT are splintered across many papers over many years. RT has also attracted repeated criticisms about assumptions, tests, and results. As a result, the nature of RT, its merits (or lack thereof), and how best to progress it, are unclear. Motivated by these issues, this paper provides a much-needed overview of RT. It further offers an evaluation of RT and explains how research on RT can improve, using a novel framework for evaluating theoretical programs. Our analysis shows that RT’s merits (or lack thereof) remain inconclusive because prior research has not proceeded systematically enough. In this light, we explain and illustrate how research can proceed more systematically.