Brian D. Christens is Professor of Human and Organizational Development at Vanderbilt University, USA, where he directs the PhD program in Community Research and Action. His research is focused on how different organizational approaches to collective action - and different interorganizational network dynamics - can lead to changes in systems that benefit communities. His research also seeks to understand sociopolitical development processes among participants in these types of change efforts. He is the author of Community Power and Empowerment (Oxford University Press, 2019).