Lean construction is increasingly adopted due to low productivity, industry fragmentation, and adversarial relationships, enhancing stability and transparency. This paper outlines future scenarios for Germany, aiding construction companies in proactive preparation. Using the scenario technique, three Lean construction scenarios were developed and compared with AI-generated results. A literature review examined Lean construction's current state, followed by identifying crucial influencing factors through megatrend analysis and a PESTEL analysis. Sustainability, digitization, and collaboration emerged as key factors. Future projections for each were developed and linked to form scenarios: A sustainability scenario which is shaped by environmental regulations and green technology for sustainability, advancements in Building Information Modeling (BIM) are shaping the digitization scenario and integrated project delivery methods form the third scenario “collaboration”. The scenarios developed in this paper support those initially suggested by an AI tool. This analysis enables construction companies to adapt oneself to future scenarios and derive actions.