This paper explores the phenomenon of journalistic interventionism among professional journalists. The paper conceptualizes what journalistic interventionism is based on several recent themes in the literature while proposing four types and dimensions of this phenomenon. The research explores how journalists professionally understand and define journalistic interventionism, how they normatively conceive of it, the types of interventions that they consider legitimate and illegitimate, and what they perceive as its possible drivers. During the interviews, journalists refer to the four types of interventionism, emphasizing the complementary, intentional, and motivational aspects behind it. They legitimize interventionism by the impossibility of complete objectivity, the nexus between journalistic interventionism and the mission of journalism, and the goal of giving voice to underrepresented groups and ideas. Journalists tend to agree with and normalize advocacy interventionism and reject partisan activism, although protest participation is also legitimized in certain contexts. Journalists attribute the motivation for interventionism to the mission of journalism, to opportunities and incentives on social media, and to professional ambitions, self-promotion and branding, and competition considerations. The conclusions discuss how journalistic interventionism relates to the scholarship on the malleability of journalistic roles, changes in journalism, and journalistic branding.