Sub-municipal government is a democratic instrument complementing traditional forms of citizen participation and as such contributing to the decentralization of the local political decision-making process. The main task of the sub-municipal government in Croatia is to serve as the consulta tion and communication mechanism within local units that parallel to local councils allows alternative representation of small communities’ interests. However, the sub-municipal government has a rather weak position in terms of autonomy, financing, transparency, size and other. Nevertheless, examples of some Croatian towns demonstrate the democratization potential of the sub-municipal government. In this paper, a survey has been conducted in the City of Rijeka (the third-largest city in Croatia). The questionnaire has been sent to all of its sub-municipal self-government units. The goal of the survey was to research their primary roles. The results have shown that the role of local activities’ initiator is the most developed role of the sub-municipal local units. They are then used to suggest further improvement of the system of the sub-municipal government in Croatia.