The transfer of responsibility for decisions and actions from humans to machines presents difficult problems for all those concerned with new concepts, their development and use. This book gives practical help by discussing the issues in the context of product design, and gives a methodology to solve them.The design cycle for autonomous systems is described, set in the context of human decision-making and the evolving ethical and legal environment. These are explained in separate chapters that will be invaluable to engineers and all the professions associated with autonomous systems.Systems engineering methods, used for weapon systems, are described. These are developed for both military and civil applications. A detailed worked example demonstrates the legal limits imposed on Lethal Autonomous Weapon Systems (LAWS) by current international law.