Ever since the participatory revolution in the 1960s, post-industrial democracies are experiencing a rapid increase in both levels and modes of citizen involvement in political decision-making. This development, which has mainly been considered to have resulted out of the process of post-modernization, has invoked an intense scholarly debate. Opinions diverged widely on how to interpret this sudden increase: Although many politicians and political scientists have welcomed these changes as strengthening the democracy in terms of “government by the people”, not all scholars shared this enthusiasm. The participatory expansion in post-industrial societies invoked also criticism and concerns about a possible crisis in Western representative democracies. The main objective of this study is to take up this discussion on the link between political involvement and democracy in post-industrial societies with the aim of finding out how “benign” the future of democracy in these societies, in the light of the recent developments in involvement, would be. Unlike former studies, however, this research is based on the premise that the quality of democracy is not only determined by the extent of citizen involvement in the political decision-making, but also by the motivations driving these activities. This premise was mainly inspired by Max Kaase and Samuel H. Barnes, who developed in the famous Political Action Study of 1979 a typology of political involvement based on the level of both political participation and political interest as the motivation behind participation. According to them, two of the resulting involvement types, namely, instrumental and expressive political involvement, are the key motivational-behavioral categories that are relevant for the stability and functioning of democratic government in these societies. A comprehensive cross-country analysis of the levels and development of these involvement types as well as their backgrounds among twelve Western post-industrial democracies has shown that many assumptions of the theories on a possible crisis of democracy cannot be verified. Yet the results have displayed also remarkable cross-country differences in involvement patterns, which calls into mind that other factors may as well contribute to the explanation of these patterns than post-industrialization and its indicators.