This book promises to be an innovative exploration of twin health and well-being, combining traditional themes with the latest knowledge in the field. It covers a wide range of topics, including the biology of twinning, management of twin pregnancies, challenges of monochorionicity, and the similarities and differences between identical twins and non-twin siblings. In addition to these areas, the book comprehensively addresses various aspects of maintaining health, well-being, and the prevention of age-related diseases. It evaluates the impact of environmental factors, lifestyle choices, and epigenetic modifications on the different trajectories observed in monozygous twins. Drawing from recent studies, including the International Society for Twins Studies and the International Conferences on "Twins" held in Budapest in 2023 and in Assisi ( Italy) in 2024 , this volume provides valuable insights into promoting individual health.  While it will undoubtedly be of great interest to obstetricians and neonatologists who frequently encounter the challenges and risks associated with twin pregnancies, this book is also a valuable resource for individuals interested in health, prevention, and specialized medicine. It offers a comprehensive study of twin development, from conception to adulthood, shedding light on the unique journey of twins and enhancing our understanding of their experiences.