Background: In the USA, 28.5% of the population is considered underrepresented minority (URM) population; however, fewer than 8 % of US' research faculty in science, technology, engineering, and mathematics (STEM) disciplines are minorities (National Research Council, Expanding underrepresented minority participation: America's science and technology talent at the crossroads, 2011). In order to diversify the faculty, Big Ten Academic Alliance's Professorial Advancement Initiative (PAI) provided high-quality professional development for URM postdocs across multiple institutions. This study is part of the larger PAI project and examined the goals and experiences of URM postdoctoral fellows in science, technology, engineering, and mathematics (STEM) disciplines. In addition, we investigated the influence of a professional development workshop on postdocs' self-efficacy to pursue grants, improve relationship with their mentor, and apply for academic jobs. Results: Our findings suggest that URM postdocs face a number of challenges in their position and lack the confidence, knowledge, and skills to pursue a career in academia. Our professional development workshops focused on developing postdocs' skills to pursue faculty positions significantly increased their self-efficacy in grant writing, improving relationship with their mentor, and applying for academic jobs. Conclusion: Our findings have important implications for postdoctoral training and providing professional development opportunities for minority postdocs in order to diversify the faculty in STEM disciplines. Future research should examine the long-term influence of workshops to prepare postdocs to pursue and be successful in academia.