Professor Walker is Vice-Chair, and Director of Graduate Studies in the Department of Sociology at UCLA. His research has investigated how corporations intervene in public life through mobilizing grassroots campaigns and partnering with nonprofit organizations, how business contexts structure the tactical choices of protest groups, and the relationship between professionalized (or “non-membership”) advocacy organizations and traditional membership organizations. He has also studied community-based organizations’ efforts to build power for underrepresented citizens, charitable giving by firms in the health and wellbeing sector, and media coverage of protest.