Elizabeth Oliver and Sarah Prager

Elizabeth Orianna Oliver and Sarah Mollie Tremper Prager are to be married Sunday afternoon at the Beachmoor, an inn in Bourne, Mass. Tracy A. Ahlquist, a friend of the couple who received permission from the Commonwealth of Massachusetts, is to officiate.

Ms. Oliver (left), 27, will take Ms. Prager’s name. She is a coordinator with the Unitarian Universalist Association of Congregations in Boston, the church’s administrative body, where she administers health insurance benefits for the organization’s staff members and for those of its affiliated congregations. She graduated from Bryn Mawr. She is the daughter of Anne Marie Oliver and Brian J. Oliver of Sandwich, Mass.

Ms. Prager, 24, is the communications coordinator for Realize Resources, a nonprofit organization in Boston that trains H.I.V./AIDS service providers. She graduated from Boston University. She is a daughter of Beverly A. T. Prager and Richard G. Prager of Simsbury, Conn.