PurposeWhile many procurement systems govern the construction sector, Design/Bid/Build is still prominent among the French building actors. The research applies Lean thinking (via a kaizen event) to the bidding phase of a building construction company to improve its bidding outputs.Design/methodology/approachThe method used in this study is “Action-Research”. A two-month preparation phase was needed to prepare for the kaizen event. The results were based on an assessment conducted after 6 months of the kaizen event. Performance was measured following selected indicators related to ‘Time’, “Economical Impact”, “Quality” and “Sustainability”.FindingsThe Lean implementation had positive side-effects on the company’s organization and strategy as well.Practical implicationsThe findings of this action-research project can be used to help researchers and practitioners assess the potential application of Lean in the bidding phase. It also provides insights into the importance of the cultural and existing practices for a successful Lean implementation.Originality/valueA few research projects investigated the application of Lean thinking in bidding as it is considered as a wasteful process. However, waste can also be organized. The research proves that bidding can benefit from Lean thinking.