This book addresses current practices in customary law. It includes contributions by scholars from various legal systems (the USA, France, Israel, Canada etc.), who examine the current impacts of customary law on various aspects of private law, constitutional law, business law, international law and criminal law.In addition, the book expands the traditional concept of the rule of law, and argues that lawyers should not narrowly focus on statutory law, but should instead pay more attention to the impact of practices on real legal life. It states that the observation of practices calls for a stronger focus on usage, customs and traditions in our legal systems the idea being not to replace statutory law, but to complement it with customary observations.