This book investigates the ethical implications of the rapid advancements in human biotechnology and the extent to which society should permit the control of human evolution. John Harris, a prominent figure in bioethics, utilizes his expertise to analyze the moral landscape created by developments such as cloning and genetic screening. He presents a framework for evaluating these technologies, balancing scientific progress against the potential for social and individual harm.

Experts recognize this work as a foundational text for understanding the intersection of bioethics and modern genetics. Readers frequently note the clarity of the author's arguments despite the complex nature of the subject matter.