Design for the Environment. With an uncapitalized "f", DfE typically refers to the U.S. EPA DfE projects and staff. With a capital "F", it is generally recognized as the more general concept of design for the environment. DFE practices are designed to be comprehensive, multidisciplinary approaches to integrating environmental concerns and constraints into product and process design procedures. DFE, in fact, marks the transition of the environmental function within firms from overhead to strategic.