In previous articles we defined an element of lean as a phase and gate structure for new product development. This assumes a waterfall approach to the project (versus agile product development).
A new product life cycle phase gate structure might entail, for example: “Definition, Concept, Design, Verification, Qualification, Production and End-of-Life”. (Your organization might decide on different phase names.)
There’s an apparent contradiction in using a waterfall project approach and calling it lean project management, however. A goal of any lean process is to work toward ‘single piece’ or continuous flow: agile product development is more like ‘single piece flow’ of information, versus waterfall which is more like ‘batch processing’ of information.