News aggregation—or the process of taking news from published sources, reshaping it, and republishing it in an abbreviated form within a single place—has become one of the most prominent journalistic practices in the current digital news environment. It has long been an important part of journalism, predating reporting as a form of newsgathering and distribution. But it has often been a poorly, or at best incompletely, understood practice. Aggregation was widespread in the 18th and 19th centuries through copying and republishing of newspaper articles in ways that sometimes showed little regard for copyright or individual authorship. But in recent decades, more sophisticated forms of aggregation have proliferated, both automated and manual, and on virtually every digital platform on which news is disseminated. Aggregation draws from the norms and values of both modern professional journalism and Internet culture and writing. That amalgam of standards and practices shapes aggregation as a hybrid practice that is built on professional journalism yet marginal within it. News aggregators’ economic effect on the online news marketplace has been intensely debated, but research has shown them to be generally helpful to the news sites they aggregate from, expanding the news ecosystem and sending readers through hyperlinks. Their legal legitimacy has also come under scrutiny, though they have encountered significantly more restrictions in Europe than in the United States or elsewhere. Professionally, aggregation is built on the practices of reporting and relies on reporting as both the predominant source of its information and the blueprint for its methods of verification. But its defining characteristic is its secondary status relative to reporting, which shapes its methods of gathering evidence as well as its professional identity and values. Overall, news aggregation plays a growing role in the contemporary news environment, though its influence is complex, multifaceted, and ambiguous.