How do internships influence the socialization and performance of accounting students employed in the tax department of a CPA firm? Previous research on accounting internships primarily focuses on auditing personnel. There is evidence in the literature that indicates audit and tax professionals have different work cultures. This paper examines the relationship between internships and subsequent professional performance of tax professionals as measured by promotion velocity and employee turnover. The human resource department, from seven regional CPA firms with similarly structured internship programs, provided performance, promotion and turnover data on employees who completed internships and employees who did not complete internships. The results of the study indicate that internships positively affect performance evaluations, promotions, and employee retention of tax professionals.