This research aims to contribute to the knowledge gap about opposition and support parties’ competitive behaviour in minority situations where no party have a majority in the parliament. Two Swedish parties - the Centre Party and the Left Party - will be examined to answer the two overarching research questions. Namely, 1) how does the competitive behaviour of parties vary in relation to a party’s role as a support party or opposition party? And 2) does the result support the cartel party thesis or the model of classic opposition? The competitive behaviour was measured in regards to counter proposals, standpoints and reservations on the governmental propositions. This was done through a quantitative content analysis of committee reports during four terms of office. The results indicate that both parties were more competitive during their time in opposition compared to in support status. This supports the model of classic opposition and rejects the cartel party thesis.