Through the past few years, the last planner system (LPS) as one of the main important methods of lean implementation in the (AECO) industry proved to improve efficiency, performance, reliability, planning and coordination. LPS can be implemented in design projects as well as in construction projects. This research reports the implementation process of the LPS as a basis for continuous improvement in the design stage. The first part is about Lean Concept definition, values and wastes; challenges faced, and Lean implementation. Second part is focusing on the last planner system, its definition and method of implementation. Third part is a case study of how LPS is implemented in managing a design project in a design consultancy firm, how to lead the lean enterprise, and how to deal with change resistance within the team.