The Eta Omicron Sigma Alumnae Chapter was organized on February 20, 1993 by Soror Paulette Davis, with assistance by Soror Inez Vanable. Sorors Denise Agnew Luvenia George, Dorothy Hoover Mary A. Johnson, Delois Jones, Zenobia Just, Helen Skelton, Jennie Walburg, Anita Wall, and Zelma Wesley originally chartered the Eta Omicron Sigma Chapter in Washington, DC. Five Sigma women worked together to bring the Sigma Torch to Southern Maryland. Under the auspices of Northeastern Region Syntaktes Felicia D. Blakeney, the chapter was relocated to Waldorf, Maryland, on December 22, 2005. The five reactivating sorors were Rebecca Hatcher, Lisa Savage, Allison Fisher, Sharon Carlton, and Tamanu Wannamaker.
Chapter Mission: Sigma Gamma Rho Sorority, Inc., Eta Omicron Sigma Chapter's aim is to enhance and develop the Southern Maryland community through community service, outreach and educational support.
Arc of Southern MD - Adopt a Family: Coordinated with The Arc of Southern Maryland, each year during the Holiday Season the Eta Omicron Sigma Chapter donates items to a family with an individual that has an intellectual or developmental disability.
Lifestyles Walk to End Homelessness: Sponsored by Lifestyles of Southern Maryland, this three-mile walk supports the annual "Safe Nights" program. The goal is to raise money and awareness about the issue of homelessness within the Charles County community.
Rhoyal Evening in Black: Held in October, this annual event is in memory of the late Soror Hattie McDaniel. The event is designed to bring awareness about breast and other cancers affecting the minority community. Information about breast cancer is collected from various health centers within the Charles County community and distributed at the event. A portion of the proceeds benefits the chapter's Cancer Awareness efforts.