This study is concerned with an urban movement and its role in urban politics. An urban movement is conceived here as an individual organization which makes urban demands whatever their levels and effects. The text focuses on the origin, the character and the effects of a housing movement in Hong Kong. An issue concerning Aged Temporary Housing Areas (ATHAs) is taken as a case study in order to throw light on the reasons why, and how, urban minorities in Hong Kong employ collective actions to protect or advance their interests. Furthermore, the author draws on the findings of this study to shed light on the theoretical discussion about the process of translating a social base to a social force.