The 21st century, like the 20th century before it, promises to be a time of extraordinary scientific growth and innovation. However, the hope for new cures and explanations about the world is often accompanied by new ethical concerns. This series examines the science behind three current fields of research and explores the implications for future scientific developments. Readers are also introduced to some of the controversies surrounding these subject areas to better understand the risks and benefits associated with modern advances. With sections devoted to significant concepts and thinkers, these books help bring to life the excitement of the discovery process.