Environmental degradation has been part of American life for centuries, and yet environmental journalism as a specialized reporting beat has only existed since the 1960s. In the ensuing decades, the environment has fallen in and out of favor as a priority for news organizations. Moreover, journalists who pursue environmental stories have long been dogged by a reputation that they are activists, a charge that delegitimizes their labor and further undermines the potential for news organizations to commit to reporting on environmental issues.  In The Environmental Beat: Inside the Struggle to Legitimize the Environment as News, Suzannah Evans Comfort examines the circumstances under which news organizations chose to invest in environmental journalism since the early 20th century, demonstrating that a combination of external social factors and internal newsroom dynamics must occur for the environment to appear as a newsworthy topic. Comfort also examines actors on the margins of journalistic legitimacy, such as newspaper outdoor columnists who wrote on the sports pages, and environmental advocacy presses that provided a far more consistent source of environmental news making than their peers in the newsroom. These low-status actors in the journalistic field embraced advocacy and rejected both-siderism in their reporting on issues of the environment. Their consistency and longevity, even as more traditionally produced news attention waxed and waned, may provide an explanation for the perception of environmental news making as fundamentally activist.  The Environmental Beat will be of interest to working journalists as well as scholars of journalism.