Lean Software Development is the application of the principles of the Toyota Product Development System to software development. Toyota has been extremely successful developing complex new vehicles, which include a vast amount of embedded software, in a very short time and always on time. This tutorial examines the underlying engineering principles Toyota uses to develop vehicles and shows how they can be applied to software development. When correctly applied, lean software development results in high quality software that is developed quickly and at the lowest possible cost. Moreover, the success of many of the practices of Agile Software Development can be explained by understanding the principles of Lean Software development.