‘By integrating key concepts such as population density from organizational ecology to International Relations, Bush and Hadden offer a fresh perspective on the evolution of the non-profit sector both in the US and globally. Their meticulous research provides insightful answers to fundamental questions, such as why certain organizations lean toward hyper-specialization and under what conditions NGOs are more likely to compete with, rather than collaborate with, like-minded organizations in crucial areas of global governance.’
                                              
                                                      Alexander Cooley - Barnard College, Columbia University
                                              
                                              ‘This ambitious and superbly readable book demonstrates how growing population density and competition influence both the founding of new INGOs, the focus of their work, choice of strategies, and overall performance. Interrogating the complex interplay between individual organizational goals and ecological pressures, Bush and Hadden explain why-even when it comes to ‘doing good’-more isn’t always better. An absolute must-read for students and scholars of transnational advocacy and organizational ecology.’
                                              
                                                      Mette Eilstrup-Sangiovanni - Department of Politics and International Studies, University of Cambridge
                                              
                                              ‘In this theoretically and empirically rich analysis, Bush and Hadden provide a much-needed examination of the landscape of NGOs since World War II. The book's interdisciplinary theory and multi-method research design are only two of its many strengths. A must-read for scholars of organizational theory, international institutions, and global civil society.’
                                              
                                                      Jon C. W. Pevehouse - Vilas Distinguished Achievement Professor of Political Science, University of Wisconsin-Madison
                                              
                                              ‘Crowded Out offers a path-breaking account of INGOs in contemporary world politics. Combining compelling theoretical innovation and impressive empirical research, Bush and Hadden demonstrate how population dynamics shape key trends in the founding, specialization, and location of INGOs - with powerful implications for their capacity to meet urgent needs.’
                                              
                                                      Jonas Tallberg - Professor of Political Science, Stockholm University