We propose a theoretical model of social change in which lobbying is a strategy available to social groups in order to influence the government on environmental taxes. Building on endogenous lobby formation, we investigate the influence of equilibrium lobby structures on the diffusion of environmentalist values. An important result of our model is to provide the conditions under which lobbying by materialist citizens entails a convergence to a fully brown society. The emergence of an environmentalist lobby implies a two-lobby structure and an upper bound on the share of environmentalist citizens, so that there is no convergence to a fully green society. We study a number of factors potentially improving the green transition: cultural mutations, social-signaling, sensitivity to pollution, and lowering organizational costs for the environmentalist lobby. Finally, we provide policy implications.