Lean is a management and design principle that emphasizes the maximization of end user value while minimizing waste. Lean principles focus producers on the end outcome of actual value delivered to the customer, while relentlessly innovating in business processes to reduce waste in production. Lean thinking changes the focus of management from optimizing separate technologies, departments, and assets to optimizing the flow of products and services through entire value streams that flow horizontally across technologies, assets, and departments to customers.