Capt. (USN ret.) and Mrs. Rhodes Boykin Jr., of Chevy Chase, Md. announce the engagement of their daughter, Katherine Douglas, to Craig Hawkins Ulman, son of Mr. and Mrs. Lewis Holmes Ulman of Woodbridge, Ct., and Washington, D.C. A fall wedding is planned.

Miss Boykin, a graduate of Randolph-Macon Woman's College (Va.), was presented at the National Debutante Cotillion and Thanksgiving Ball of Washington in 1972 and was a member of the White House Intern Program of 1974. She is a public affairs officer at the U.S. League of Savings Associations in Washington, D.C. Her father is a partner with Booz, Allen and Hamilton, Inc., in this city, and she is the granddaughter of the late Mr. Rhodes Boykin and the late Mrs. Elizabeth Going Boykin of Birmingham, Ala., and of the late Mr. and Mrs. George Whitfield Jarrett of Chattonooga, Tn.

Mr. Ulman, an alumnus of St. Albans School, is a Phi Beta Kappa graduate of Harvard College where he was a member of the Phoenix-SK Club. gA 1973-74 Frank Knox Fellow at Megdalen College in Oxford, he graduated from Harvard Law School in 1977. Mr. Ulman is associated with the Washington, D.C. law firm of Hogan & Hartson. His father is vice-president and general counsel of the Southern New England Telephone Co. and his late grandparents are Mr. and Mrs. Leon S. Ulman and Mr. and Mrs. John F. Preston -- all of this city.