Final answer:
The interests of service users can be represented through interest groups that band individuals together to influence policy, and by elected officials who adopt either a delegate model, directly conveying their constituents' wishes, or a trustee model, using their judgment to decide on behalf of their constituents.
Step-by-step explanation:
Two ways that the interests of service users are represented include: through the actions of interest groups and by the models of representation used by elected officials. Interest groups, such as labor unions and professional organizations, provide an avenue for individuals to join together and claim representation for their collective interests. They often provide information and expert testimony to policymakers, influencing decisions and potentially generating public support for their causes.
Regarding elected officials, the models of representation they adopt can significantly affect how they represent their constituents. One model is the delegate model, where legislators act as a mouthpiece for the explicit preferences of their constituents. The other is the trustee model, where representatives use their judgment to make decisions they believe are in the best interest of the people, considering a wide array of factors, including party consensus, powerful interests, and national trends.