A considerable number of studies have been actualized on the integrative mechanisms in new product innovation. Most of these studies have focussed on functional integration, especially R&D-marketing interfaces, as a unit of analysis. Studies have pointed out that most innovations is old science rather than new discovery. The most notable Japanese products did not involve any discontinuous innovations, but imitative and incremental innovations However, not much is known about the use and effectiveness of interfacing mechanisms in imitative projects. The research on imitation management, especially at the project-level leaves much to be desired. The aim of the study is to understand various integrative mechanisms used and the challenges faced in adopting them in different imitation environments. Using case-study methodology sixteen successfully completed imitation projects from ten different companies were investigated from the view point of integrative mechanisms used. Based on project scope (complexity) and technological uncertainty, we classify imitative product developments into four types, type I, type II, type III and type IV. Based on the categorization and clustering we identified four interface mechanisms, viz., structural integration, cross-functional team, review systems, processes, and individual integrators. Type I projects with low technological uncertainty and scope appear to rely more on individual integrators. Type II projects related to higjh project scope and low technological uncertainty environments seem to rely on structural integration. Cross-functional teams and review mechanisms are used whenever the project complexity is higjh. Scope of the project seems to define the use of particular interface mechanisms rather than the technological uncertainty. Managerial challenges in using different integrative mechanisms is discussed.