Book excerpt: Key Concepts in Philosophy is a series of concise, accessible and engaging introductions to the core ideas and subjects encountered in the study of philosophy. Specially written to meet the needs of students and those with an interest in, but little prior knowledge of, philosophy, these books open up fascinating, yet sometimes difficult ideas. The series builds to give a solid grounding in philosophy and each book is also ideal as a companion to further study. Western philosophy has always placed questions of ethics - of how to live well - centre stage. Ethics: Key Concepts in Philosophy is the ideal introduction to the subject. It offers thorough analysis and explication of six core concepts in moral philosophy: agency; reason; happiness; obligation; character; responsibility. The book covers all the major moral theories to have emerged from the Western tradition, and pays close attention to those philosophers who have made significant contributions to ethics. In addition to the six central themes, the text also discusses such key topics in ethics as relativism, egoism, naturalism, autonomy, objectivity, religion and integrity. The book concludes by looking at the challenges to moral philosophy posed by recent technological and social change. Philosophy undergraduates will find this an invaluable aid to study, one that goes beyond simple definitions and summaries to really open up fascinating and important ideas and debates.