The document discusses social commerce and how brands can engage customers on social media. It identifies two types of brand engagement: thick engagement which is sustainable, meaningful and authentic; and thin engagement. It then lists four reasons customers care about social media - social recognition, belonging to a group, developing their identity, and learning and creating. The document suggests that brands build engagement by addressing these customer motivations and by removing effort from key interactions, keeping purchase paths short from social interactions. It provides examples from Burberry and The Conran Shop of building engagement.