This document discusses group buying in China. It notes that the group buying sector generated 500 billion yuan in 2010 and saw a large growth in sites from 4 to nearly 1,700 between 2009 and 2010. Group buying works by offering limited-time deals on a website, with discounts triggered only if a minimum number of purchases is met. However, consumer retention is a challenge given the one-off nature of deals. The document also provides an overview of a company called SinoTech Group and its offerings in digital marketing and social media consulting.