The microaggression concept has recently galvanized public discussion and spread to numerous college campuses and businesses. I argue that the microaggression research program (MRP) rests on five core premises, namely, that microaggressions (1) are operationalized with sufficient clarity and consensus to afford rigorous scientific investigation; (2) are interpreted negatively by most or all minority group members; (3) reflect implicitly prejudicial and implicitly aggressive motives; (4) can be validly assessed using only respondents’ subjective reports; and (5) exert an adverse impact on recipients’ mental health. A review of the literature reveals negligible support for all five suppositions. More broadly, the MRP has been marked by an absence of connectivity to key domains of psychological science, including psychometrics, social cognition, cognitive-behavioral therapy, behavior genetics, and personality, health, and industrial-organizational psychology. Although the MRP has been fruitful in drawing the field’s attention to subtle forms of prejudice, it is far too underdeveloped on the conceptual and methodological fronts to warrant real-world application. I conclude with 18 suggestions for advancing the scientific status of the MRP, recommend abandonment of the term “microaggression,” and call for a moratorium on microaggression training programs and publicly distributed microaggression lists pending research to address the MRP’s scientific limitations.