Allegedly, the new green and left parties that were established in Western Europe during or after the 1960s tend to be characterized by informal but significant links with social movement organizations. In contrast, weak links or virtual lack of such connections is often seen as one of the enduring characteristics of the new populist (radical) right parties. However, there are both empirical and theoretical reasons for examining these conventional wisdom(s) more closely. To date, only limited evidence is available on this aspect of new European parties in general. Examining Norway's successful new left and populist right party, and based on rich original data, this case study adds to our knowledge in several ways. The analysis reveals that the socialist left has even closer and more wide-ranging relationships with interest groups than traditionally suggested and that the Progress Party enjoys organized contact with various interest groups. Since these parties are only two, and not necessarily quintessential examples of the party families in question, the results cannot overturn the conventional wisdom, but they nonetheless question and supplement it by throwing light on the conditions favouring the development of stronger, and more varied, links to interest groups. Together with other presumably ‘atypical’ party examples mentioned in scholarly literature, the case of Norway calls for further empirical investigation. Finally, with an eye to future comparative research, the possible explanations for these findings are briefly discussed.