Social networking has become global based as it is on the Internet. Less certain has been its transformation into sustainable businesses models. Most SNS have either disappeared or their market share has been absorbed by one of a very few global SNS, notably by Facebook by 2011.
But how sustainable is an SNS like FB? To answer this question this paper looks at 3 issues: (1) how FB rose to its present dominant position and why others fell short; (2) what are the business models behind SNS; (3) and how sustainable are they?