Survey participation, electoral participation, and political interest have been given wide attention in the research literature, but no one so far has combined these three variables in one model. Taking the social isolation-hypothesis as our starting point, we developed a model with one factor, social involvement, as the common factor underlying these three types of participation. We reviewed the literature and concluded that we had to include a second underlying factor: attachment to society. Using a new data set, gathered on the occasion of the 1998 Dutch national elections and including validated voter turnout measures, we were able to test the model. After making some adaptions, we found a model with a satisfactory fit. The results show that, by including social involvement and attachment to society as mediating variables, we can reach much higher levels of explained variances of survey and electoral participation than we can with traditional models. The results also add to our understanding of the relationship between survey and electoral participation and political interest.