Of wide interest is announcement of the engagement of Miss Sandra day to John Jay O’Connor III, son of Dr. and Mrs. J.J. O’Connor, San Francisco, Calif.

The betrothal is being announced by the bride-elect’s parents, Mr. And Mrs. Harry A. Day of the Lazy B Ranch near Lordsburg, N.M. The couple will be married on Dec. 20.

Miss Day attended Radford School for Girls here and was graduated from Austin High School where she was a member of National Honor Society and active in school affairs.

She has two degrees from Stanford University, having received a BA in economics in 1950 and a LLB in law in June of this year.

The bride-elect was elected to the Order of the Coif, legal honorary society, and has served as a member of the Stanford Law Review. In her senior year she was president of Union Unit and a member of Cap and Gown honorary society.

She is the granddaughter of Mrs. W.W. Wilkey of El Paso and the late Mr. Wilkey, prominent cattleman of the Southwest. Her paternal grandparents, the late Mr. And Mrs. H.C. Day, established the Lazy B Ranch in 1880.

Miss Day accompanied her family on a five-week trip to Alaska in June, after which she returned to Stanford to study for the California bar examination, which she has just taken in San Francisco.

Mr. O’Connor is the grandson of Mrs. J.J. O’Connor of San Francisco and the late Dr. O’Connor, who founded St. Francis Hospital there.

The prospective bridegroom is a graduate of Stanford University and is now studying for a law degree there which he expects to receive in June. He is affiliated with Delta Upsilon Fraternity, is a member of Phi Delta Phi, legal fraternity, and is a member of the Stanford Law Review.

The young couple will establish their home in Palo Alto until June, after which the bridegroom will enter military service.