Play Fighting considers the possible benefits of play for humans and animals. This book is divided into two main topics—animal play and human play. In these topics, this text specifically discusses the definition, evolution, and function of play; criteria of chasing and play fighting; function of laughter in human play; and spurious correlation between exploratory and playful species. The surplus energy and catharsis theories of play; vestibular stimulation acting as a reinforcer; function of mother-infant play; and properties of play-fear and serious-fear stimuli are also elaborated. This compilation likewise covers the puzzling blind spots of child psychology; play and child rearing; and play fear of "monsters. This publication is a good source for students and individuals interested in the survival value of play for animals and healthy development of children.