Research from industrial and organizational (I-O) psychology indicates that outside of K-12 education, employees' sense of fit with their organizations is often associated with job satisfaction, performance, commitment, and retention. Person-organization (P-O) fit has been conceptualized as the degree of congruence between an individual's values, goals, and/or cognitive skills and abilities and the characteristics or requirements of their workplace. This essay reviews research from I-O psychology on how P-O fit predicts key outcomes for workers outside of K-12 education and discusses recent studies of P-O fit and teacher commitment and retention. We then theorize ways in which P-O fit can be used in research on teachers' instruction, using research on teachers' enactment of ambitious mathematics instruction as an example. Finally, the essay concludes by identifying directions for future research.