Social media (Web applications supporting communication between Internet users) empower current activist groups to create records of their activities. Recent digital collections, such as the digital archives of the Occupy Wall Street movement and the Documenting Ferguson Project, demonstrate archival interest in preserving and providing access to activist social media. Literature describing current practices exists for related topics such as Web and social media archives, privacy and access for digital materials, and activist archives. However, research on activist social media archives is scarce. These materials likely present subject- and format-specific challenges not yet identified in peer-reviewed research. Using a survey and semistructured interviews with archivists who collect activist social media, this study describes ethical challenges regarding acquisition and access. Specifically, the respondents were concerned about acquiring permission to collect and provide long-term access to activist groups' social media. When collecting social media as data sets, archivists currently intend to provide moderated access to the archives, whereas when dealing with social media accounts, archivists intend to seek permission to collect from the activist groups and provide access online. These current practices addressing ethical issues may serve as models for other institutions interested in collecting social media from activists. Understanding how to approach activist social media ethically decreases the risk that these important records of modern activism will be left out of the historical narrative.