The electoral rise of the Belgian regionalist party New-Flemish Alliance (N-VA) from scratch to the country’s largest party is remarkable. We explore here to what extent the party has shifted in ideological terms compared to its less successful predecessor VU. We make use of party member survey data (a dynamic indicator of a party’s position). We distinguish three factors that impact on parties’ positions: institutional reforms, the influx of new members and changes in the internal power distribution. The results show a clear change: on each of the five policy dimensions (centre-periphery, socio-economic, moral-ethical, post-materialist and migration issues), significant differences could be found.