Welner's work examines the use of research in policymaking, the intersections among education-rights litigation and educational-opportunity scholarship, and the school-change process associated with equity-focused reform efforts. He has authored or edited eight books along with 80 articles and book chapters. Welner has received the American Educational Research Association's Early Career Award (in 2006), for best journal article, and has been designated an AERA Fellow. He holds a B.A. in Biological Sciences from UCSB, and a J.D. and Ph.D. from UCLA.