The editors of this volume are faculty members in the Department of Mathematics at the University of Extremadura, Spain. They form a research group with a strong focus on the probabilistic and inferential aspects of branching processes, as well as their applications—particularly in Population Dynamics, Genetics, and Epidemiology. Their academic contributions include the supervision of numerous doctoral dissertations and the publication of a substantial body of research in the field. In addition to their research activities, they have organized six editions of the International Workshop on Branching Processes and Their Applications (IWBPA), and have participated in a wide range of national and international scientific meetings.