Stateless Nationalist Regionalist Parties (SNRPs) are widely considered as mainstream political actors, and their ideological and strategic development in this regard has been well documented by scholars. However, little attention has been paid to how party elites view such processes. Adopting a comparative case study approach, this article looks at the case of Plaid Cymru and the Scottish National Party (SNP), both of whom entered government for the first time in 2007. Drawing on original and extensive elite interview data, the article examines how elites in both parties attempted to use the transition to government to portray their respective parties as mainstream and credible. The article finds that this aspiration is driven largely by a desire to change historically embedded stereotypes, but also, in the case of the SNP, to further the party’s primary goal of Scottish independence. In the case of Plaid Cymru, having to become a junior coalition partner meant that the party felt obliged to take up stereotypical portfolios which undermined, in part, the purpose of governmental participation for some elites.