This chapter was published in the "Fiscal inclusive development: Microsimulation models for Latin America" book, where it is presented a microsimulation model that has been developed for Chile with the explicit purpose of determining the distributive impacts of changes in tax policy and social spending. It is a free-access model, meaning that it can be used by all those interested in public policy issues. Along these lines, the model has a user-friendly interface that facilitates its use on the part of interested parties.