(Oxford University Press) This book explores the nature of moral development, human behavior, and social interconnections by comparing, contrasting, and going beyond the key theories of preeminent thinkers Lawrence Kohlberg, Martin Hoffman, and Jonathan Haidt. This third edition pays more attention to the work of Jonathan Haidt, and includes a new foreword by David Moshman. Gibbs is a professor of developmental psychology at The Ohio State University.