The Eugenic Marriage Volume 4 (of 4): A Personal Guide to the New Science of Better Living and Better Babies is the concluding volume in a comprehensive series by Dr. W. Grant Hague, originally published in the early 20th century. This book delves into the principles and practices of eugenics as they relate to marriage, family life, and the upbringing of children, reflecting the era's fascination with heredity, health, and social improvement. Volume 4 continues the series' mission to educate readers-particularly prospective and current parents-on how to apply scientific knowledge to ensure the birth and development of healthier, stronger, and more capable offspring. In this volume, Dr. Hague addresses a wide range of topics, including the physical, mental, and moral preparation for parenthood, the importance of proper nutrition and hygiene, and the influence of heredity and environment on child development. He offers practical advice on the selection of marriage partners, emphasizing the significance of genetic compatibility and the avoidance of hereditary diseases. The book also explores the responsibilities of parents in shaping the character and well-being of their children, advocating for a holistic approach to family life that integrates scientific understanding with ethical considerations. Throughout, The Eugenic Marriage Volume 4 is characterized by its detailed guidance, case studies, and references to contemporary scientific research. It serves as both a manual for individuals seeking to improve their own lives and a broader call to society to embrace eugenic principles for the betterment of future generations. While the ideas presented reflect the values and beliefs of its time, the book provides valuable historical insight into early 20th-century attitudes toward health, heredity, and social progress.