You might find some of these reports useful. Some reports are held as PDF documents within the site and others link to other sites.

Global Impact Investing Network (GIIN)
Global Impact Investing Network (GIIN) network are releasing their report on The State of Impact Measurement and Management Practice . The report provides a comprehensive survey of the state of...
JP Morgan, Rockefeller Foundation, Global Impact Investing Network (GIIN)
Impact investing offers a new alternative for channeling large-scale private capital for social benefit. With increasing numbers of investors rejecting the notion that they face a binary choice between investing...