In a gradual but unending process, the law changes society, and society changes the law. This constant impact of one on the other is a product of human behavior and social interaction. The interrelationship of law and society makes it impossible to examine the effects of law on society without considering the reverse effects. Consequently, this entry will first consider briefly the ways society affects the law and then examine the law's effect on society. It will do this from the perspectives of the new institutional economics, emphasizing the importance of norms of cooperation, although other perspectives could result in different but just as useful analysis.