Social media platforms (SMP) are increasingly important for news organizations to reach (wider) audiences. The accompanying platformization of journalism has raised concerns that the adaptation to social media characteristics leads to trivialization and softening of news. Often triggered by these normative considerations, journalistic content production for social media has attracted much scholarly attention. To date, however, these studies lack synthesis. To fill this research gap, this paper reports on a systematic literature review (SLR) of 156 publications to summarize and discuss current knowledge about how news organizations select, edit, and coordinate content for SMP. The results show that content is not generally softened on SMP such as Facebook, Twitter, or Instagram. Rather, news organizations develop strategies to balance their professional standards with social media characteristics. Differences appear, among others, in organizational traits such as revenue model and between SMP. Building on these results, the study concludes with paths to develop future research.