The initiative of writing this book has the purpose of sharing the knowledge and work experience of the last 15 years or so in the Policy and Program Evaluation Cell (CAPP) of the Etene, at Banco do Nordeste do Brasil S.A. (BNB). I present this systematized knowledge on results and impact evaluation and on the experience of the BNB in this process, as a symbolic form of thanks for these years of work and individual and collective learning at the BNB. Experience that I now share inside and outside the walls, as I like to refer to, respectively, the internal and external world of the Banco do Nordeste.