According to Lyman Tower Sargent, utopias are repositories for individual and collective hopes and fears, which sometimes unleash energies that can achieve at least part of what is hoped for. The Australian green bans movement of 1971-75 can be understood as a utopian project in this sense. During this period, the construction workers organized in the New South Wales branch of a labor union, known as the Builders Labourers' Federation, refused to work on ecologically or socially harmful projects and publicly argued for their collective right to socially responsible labor. Coining the term "green bans" to describe environmentally motivated withdrawals of labor, they halted projects worth five billion Australian dollars at 1970s prices. When enthusiastic resident action groups mobilized in support of these bans, the union grew into the core of a more general social movement. The success of the green bans movement sugg ests that the power of subversive imagining can be especially effective if coupled with the power of workers at the point of production. The movement's basic premise—that workers, acting in the general public interest, should decide what can be built and where—represented a direct challenge to the dominant power relations. Ultimately, such impossible demands could not be conceded either by the employers or by the state. But the practical effects of this utopianism nonetheless secured substantial environmental improvements, which brought the green bans activists significantly closer to their dreams.