John and Lana Nuessen of Mount Sterling have announced the engagement of their daughter, Jennifer Ann Nuessen of San Francisco, to John James Vrionis Jr. of San Mateo, Calif. He is a son of John and Lori Vrionis of Roswell, Ga.

The bride-elect graduated in 1997 from Brown County High School and in 2001 from the University of Illinois. She is employed in pharmaceutical/biotechnology consulting.

The prospective bridegroom is a 1997 cum laude graduate of Harvard University. He is employed by Venture Capital.

The couple will be married May 31 in Quincy.