When considering alternatives, a classic question is whether they can be scaled up beyond a proof of concept. In the case of squatting, activists have tried this and this chapter taps into this experience. It is based on evidence from the Netherlands, especially Amsterdam and the US, especially New York City. The Netherlands is interesting because squatting grew to be widespread for a relatively long time. In the US, squatting was possible but it was much less sustained. Also the context is different, in the US there is what Esping-Anderson (1990) calls a liberal welfare state regime. The Dutch welfare state regime can be seen as combination of the social democratic and paternalistic types. The history of squatting is quite complex, especially in the Netherlands because there was such a large and variegated movement. A book chapter can only cover a small part of it; this chapter focuses on the question of how squatting can grow to encompass more people, become more durable or entail greater cultural and economic change. It also addresses limitations and mechanisms that can force squatting into a decline. Below, I will examine various episodes in the history of squatting in the Netherlands and the US. First I will discuss some theoretical considerations that relate to movement growth.