Much of the research on online participation area focuses on citizen participation or social movements, while the internal processes of political parties have so far been neglected. Focusing on the introduction of online participation methods for internal democratic decision-making processes in the Green Party Germany, this paper will address this gap. Specifically, it will investigate the launch of an online verification process for members’ submission and support of proposals to the party assembly. This process both supports and challenges the strong grass-roots mentality of the party: theoretically access is maximised, while participation costs for certain groups may be increased. Given that all members have the right to submit proposals and that assemblies are unable to cope with thousands of submitted proposals, the party faces a dilemma. It needs to find a middle ground between effective and efficient participation on the one hand while simultaneously encouraging members to participate. Furthermore, the party needs to avoid overloading their processes to the degree that decisions are made without knowledge about what is being decided. This paper will discuss the expectations and conflicts related to the introduction of the new online process. In particular it addresses the expected costs and benefits of facilitating online participation, including the potential for changing or reinforcing the current experience of participation, and the risk of perpetuating biases relating to online access. The paper will be based on preliminary data, in particular interviews and focus groups with selected members.