In the course of election campaigns, voters pay only selectively attention to particular aspects of political problems. Such selective attention is necessary because the costs of becoming competent on many political problems are great. Normatively, however, such selective attention is not desirable because it lowers the chance that voters will reach well-balanced and competent decisions. This contribution establishes the aspects of the four most salient problems from the 2015 Swiss federal election campaign: immigration, welfare, the economy and European integration. It further reveals that selective attention is higher among those who are interested in politics and who learn problem-specific information on salient problems, and lower among those who are well-educated, who engage in personal discussions, who use traditional media, and who learn problem-specific information on less salient problems. Finally, it concludes that selective attention should be avoided in order to strengthen the citizens' level of information on political problems.