The goal of digital manufacturing is to provide the manufacturing community with solutions to create, validate, monitor and control agile, distributed manufacturing production systems geared towards build-to-order and lean production. The scope of Digital Manufacturing has evolved recently to include Computer Aided Process Planning (CAPP); Computer Aided Production Engineering (CAPE); a Manufacturing Data Base which contains product data, process data, manufacturing resources (PPR); generation of executable programs for automation; the generation of work instructions for workers on the shop floor and the feedback of manufacturing performance data from the shop floor. Digital Manufacturing is a 3D computer environment that has only become possible because the product data and tooling data are now available in 3D CAD. This paper discusses the methodology of applying Digital Manufacturing from the initial concept design phase of both product and production processes, through detail design and validation, to both implementation on the shop floor and the constant monitoring the shop floor performance data to support continuous improvement activities. Because up to 60 percent of the value of automobiles and fighter aircraft are sourced from suppliers, the Digital Manufacturing environment must be accessible across the supply chain to support today's B2B method of doing business.