Lean manufacturing practices and sustainability are conceptually similar in that both seek to maximize organizational efficiency. Where they differ is in where the boundaries are drawn, and in how waste is defined. Sustainability expands the definition of waste to include the wider range of consequences of business actions including environmental and social consequences. Lean processes are inherently less wasteful and in this sense promoting lean processes can help organizations become more sustainable.
It can be said that lean is green. The obvious benefits of green and lean are energy savings, productivity savings, and savings from improved utilization of materials. They can also lead to innovations that involve creation of new products out of waste materials.