Social lending using peer-to-peer (P2P) platforms is not a new concept, as informal lending between friends and family has long existed. However, the use of social media and online platforms is a new development that is growing rapidly. P2P lending platforms like Prosper and Zopa have originated over $160 million in loans in just a few years. Studies predict that the P2P lending market in the US could grow to $5.8 billion by 2010, and social banking platforms may capture 10% of the worldwide retail lending market by that year. This document examines the history and growth of social lending using online P2P platforms.