Series 1 is organized into three major subcategories of antinuclear protest groups: local organizations (e.g. AEC, Clamshell, etc.), domestic organizations in the US at large, and international organizations. The local organizations are the main core of this series, and include the groups most closely related to antinuclear protests against the Seabrook Station Nuclear Power Plant specifically, and in New England more generally. These local organizations, while separate entities, were often closely interrelated and included overlap among both participants as well as founders. The domestic and international organizations reflect the wide reach of antinuclear sentiment in the 1970s and 1980s, and are sorted by state and country of origin respectively. The domestic and international groups often communicated with the local organizations via newsletters and correspondence, seeking contact, support, and advice from Clamshell founders and participants, and other local organizations.

Series 2 contains documents about the Seabrook occupation. Of special note are documents that outline the Clamshell Alliance's meeting notes, "occupier's handbook", planning, promotion, songs, and other correspondences related to the Seabrook protests and occupations between 1977-1980. Testimonials of protesters that were arrested, articles about Seabrook by Steve Diamond and Harvey Wasserman, photographs of the Seabrook occupation in 1977, published articles about the Seabrook protests, letters of support, and NRC and EPA reports about Seabrook are included in this series. More content about Seabrook is in the AEC collection (MS 586).

Series 3 consists of records relating to four major organizers and activists involved in multiple antinuclear organizations and movements: Steve Diamond, Anna Gyorgy, Sam Lovejoy, and Harvey Wasserman. The folders relating Diamond include personal correspondences about REMS, antinuclear protests, and letters from Raymond Mungo. More personal documents can be found in Series 1. Gyorgy, a member of the Montague Farm community, was an early leader in the protests against nuclear energy, helping to organize the AEC, and a founding member of the coalition that founded the Clamshell Alliance. The folders relating to Gyorgy include drafts and correspondence related to the publication of her book, NO NUKES: Everyone's Guide to Nuclear Power (South End Press 1979/1981), general correspondence with various individuals representing antinuclear and related groups worldwide, financial documents, and papers and notes from the Society for International Development (SID) Conference in Rome in 1985. The balance of the Gyorgy Papers are housed at SCUA with the Anna Gyorgy Papers, 1974-1988 (MS 631), and at Smith College. The folders relating to Lovejoy include published articles about nuclear energy, personal and official correspondences, and transcriptions from courtroom testimonials about nuclear power plants. The folders relating to Wasserman include drafts of articles he wrote on antinuclear topics, research documents, and correspondence.

Series 4 consists of ephemera items, such as antinuclear stickers, buttons, t-shirts, posters, photographs, comic books, song lyrics, and 45 rpm records. Of interest are stickers and buttons (in various languages) from various protests and gatherings.

Series 5 consists of undifferentiated newspapers and other publications (complete and partial) as collected by the members of the various local organizations. They were used for research into antinuclear, clean energy, and antiwar topics, as mementos of publicity related activities, and received unsolicited from other organizations both domestic and international. Of interest are domestic and internationally published antinuclear organizations newsletters (e.g. Abalone Alliance Newsletter, Liberation News Service). This series is incompletely processed and awaits inventorying.