The Three Rs tenet guides scientists on the ethical use of animals in science:
Replacement refers to methods which avoid or replace the use of animals in an area where animals would otherwise have been used
Reduction refers to any strategy that will result in fewer animals being used
Refinement refers to the modification of husbandry or experimental procedures to minimize pain and distress
Ethics in Research: A Science Lifecycle Approach by 
The Oxford Textbook of Clinical Research Ethics by
The Oxford Textbook of Clinical Research Ethics is the first comprehensive and systematic reference on clinical research ethics. Under the editorship of experts from the U.S. National Institutes of Health of the United States, the book's 73 chapters offer a wide-ranging and systematic examination of all aspects of research with human beings. Considering the historical triumphs of research as well as its tragedies, the textbook provides a framework for analyzing the ethical aspects of research studies with human beings. Through both conceptual analysis and systematic reviews of empirical data, the contributors examine issues ranging from scientific validity, fair subject selection, risk benefit ratio, independent review, and informed consent to focused consideration of international research ethics, conflicts of interests, and other aspects of responsible conduct of research. The editors of The Oxford Textbook of Clinical Research Ethics offer a work that critically assesses and advances scholarship in the field of human subjects research. Comprehensive in scope and depth, this book will be a crucial resource for researchers in the medical sciences, as well as teachers and students.
