The primary function of a parliamentary system in government is to facilitate the formation of a government that is accountable to the legislature. In this system, the executive branch derives its legitimacy from the legislative branch and is dependent on its support. This fosters a closer relationship between lawmakers and the government, promoting cohesive policy-making. Additionally, parliamentary systems often feature a prime minister who is the head of government, enabling swift decision-making and response to issues. The system enhances representation and can lead to more stable governance through coalition-building among political parties.