How do institutional factors and party characteristics shape parliamentary opposition in EU politics, ask Thomas Persson, Christer Karlsson, Felix Lehmann & Moa Mårtensson in this recently published article. They introduce the idea that opposition can either take the form of expressing critique (e.g., influencing or shaping policy-making) or providing alternatives (e.g., providing different policies or methods), and argue that the strength of oversight mechanisms as well as Euroscepticism of a party determines which form of opposition MPs choose to use. To test this argument, Thomas, Christer, Felix and Moa analyse more than 7,500 statements of MPs Denmark, Germany, Ireland, Sweden and the United Kingdom during plenary sessions and deliberations during European Affairs Committee meetings. The analyses demonstrate that in the absence of strong oversight mechanisms, MPs primarily make use of opposition in form of critique. Additionally, and unsurprisingly, MPs belonging to Eurosceptic parties are champions of opposition both in form of expressing critique and presenting alternatives. Most interestingly, however, the results show that in contrast to members of Eurosceptic parties who engage in oppositional behavior irrespective of institutional contexts, MPs from Europhile parties seem to regard formal oversight mechanisms partly as a substitute for expressing opposition. With these findings, the article provides a more nuanced picture about the drivers of oppositional behavior in EU politics, it prompts future research to take into account the interplay between institutional set-ups and party characteristics when analyzing parliamentary opposition.