The seminar offers a preliminary introduction to  portfolio optimization theory applied to sustainable investments. The aim is to show, in a simple and intuitive way, how mathematics can help us to understand the balance between risk and return, with a particular focus on sustainability. Through a simulation software (MATLAB), students will construct portfolios composed of securities with different levels of sustainability. They will decide how to invest their capital according to their own "green" preferences and observe how these choices affect return and risk. In this way, they will learn to handle the trade-off between environmental responsibility and financial results.