The aim of this book is to determine the effects of participatory budgeting processes and to identify the success factors that play a significant role in them. To answer these questions, an evaluation framework is developed based on the current state of research and modern theories of democracy, which is used to analyze ten participatory budgeting projects and evaluate them by a total of eight selected experts. The results of the study are then presented, identifying the success factors and demonstrating the extent to which they influence the effects of participatory budgeting processes. The empirical investigation has shown that participatory budgeting processes can help provide citizens with direct and indirect opportunities to influence political decision-making, as well as increase the effectiveness and efficiency of administrative actions.