Robert and R. Elizabeth Swartz of Butler are pleased to announce the engagement of their daughter, Emilly Swartz, to Joseph McMullen, the son of Joseph and Deborah McMullen of Brockton, Mass.

The bride-to-be is a 1996 graduate of Butler High School and a 2000 graduate of Villanova University, earning a degree in chemical engineering. She is a chemical engineer for BEK Engineering in Wilmington, Del.

Her fiance is a 1996 graduate of Boston College High School; and a 2000 graduate of Villanova University, where he earned a bachelor of science degree in chemical engineering. He also earned a master of business administration degree in 2004 from Villanova. He works at Invensys in Boothwyn.

A Dec. 4 wedding is planned.