This thesis analyzes the optimization of the concession period in Public-Private Partnership (PPP) projects, focusing on the Build-Operate-Transfer (BOT) contractual model. The concession period determines how long the private partner operates an infrastructure to recover investment costs and earn a return, before transferring ownership to the public sector. Its duration is a critical variable: if too short, the project may be financially unsustainable for private investors; if too long, it may undermine public welfare by limiting government control. The research provides a comprehensive review of existing methodologies for determining the optimal concession length, including traditional financial tools such as the Net Present Value (NPV) model and more advanced techniques that incorporate uncertainty and negotiation dynamics.