Through nature conservation practices, farmers can strongly enhance nature quality and biodiversity in rural areas. In this paper, the social psychological underpinnings of farmers' nature conservation practices are investigated using the Theory of Planned Behavior, to which the concepts of self-identity and personal norms were added. A distinction is made between nature conservation practices done on a non-subsidised basis and nature conservation practices for which farmers receive some form of remuneration from the Dutch government. Eighty-five arable farmers participated in our survey. Results show that our model explains more variance in the intention to perform non-subsidised than subsidised nature conservation practices. Also, the concepts of self-identity and personal norms appear to be related to the intention to perform non-subsidised, not subsidised conservation.