Social intrapreneurship is the action of a social intrapreneur. A social intrapreneur is someone who works to develop and promote practical solutions to social or environmental challenges and acts as a social entrepreneur inside a major organization. A social intrapreneur might also be called a Corporate Social Entrepreneur
The definition of a social intrapreneur was described by two landmark reports on the subject. Net Impact, with the support of eBay, wrote Making Your Impact at Work. SustainAbility, with the support of IDEO, Skoll Foundation, and Allianz, wrote The Social Intrapreneur: A Field Guide for Corporate Changemakers.
BeDo held the first conference on the subject, BeDo Intra 2009, around the Social Capital Markets Conference (SOCAP09) in San Francisco.
Ashoka Changemakers in partnership with Accenture initiated in the Fall of 2012 the first network exclusively for social intrapreneurs called the League of Intrapreneurs. The League is a "movement brand," cooperatively owned by a number of stakeholders. 
- Hemingway, C.A., Personal Values as a Catalyst for Corporate Social Entrepreneurship, Journal of Business Ethics, 60(3), pp.233-249. 2005.