Newly collected data on India’s textile industry over the years 1921–38 show strike rates far higher than those observed in the British or U.S. textile industries when they were at a similar stage of development, despite an absence of formal union organization or state support for collective bargaining. Colonial India’s high strike frequency is hard to account for in terms of current theories of strikes and collective action in general. The author believes that these data may point to the important role of social norms of cooperation in sustaining collective action