The aim of this chapter is to introduce the aim and structure of the book. Specifically, the aim of the book is to build a bridge between corporate social responsibility (CSR) and sustainable finance in financial markets. Classic CSR topics have been investigated in the light of a modern conception of sustainability. The book is organized in two main blocks. The first block emphasizes four relevant topics in the CSR panorama of financial institutions: banks remuneration practices; human capital disclosure; the impact of environmental performance on banks, and finally, the institutional investors’ attitude towards socially responsible investments (SRIs). The second block looks to CSR practices within the financial markets and discusses risk-return profiles of SRI and non-SRI indexes in different time frames; it investigates whether thematic social responsible funds obtain different risk-return than traditional funds, and finally, assesses whether equity crowdfunding could foster social innovation.