​Eileen Smitheimer has provided lighting and sound designs for theatre productions in regional, university, and civic organizations.  Her design credits include The Walnut Street Theatre, The Arden Theatre Company, The Huntington Theatre Company, Delaware Theatre Company, Surflight Theatre, Queens Theatre in the Park, The Russian Ballet, Drexel Institute, Allentown College, Tennessee Williams Fine Arts Center, The Miniature Theatre of Chester, Hope Summer Repertory, Music Theatre North, City Theatre, First Stage, Southern Methodist University, Enchantment Theatre Company's world-touring magic show A Magical Fantasy, and the American tour of the Bolshoi Ballet. She worked for four years as Sound Designer/Engineer and Master Electrician at Southern Methodist University teaching courses in sound design/engineering and as a freelance engineer/designer at McFarlin Auditorium.

Ms. Smitheimer received her B.A. and E.E.T. degrees from Purdue University. She serves as a Vice–commissioner of the Sound Commission of the United States Institute for Theatre Technology (USITT), is a member of the International Organization of Scenographers, Theatre Architects and Technicians (OISTAT) working group on Sound Design, and was a participant in the OISTAT Colloquium on Theater Sound Design, Royal National Theatre, London, England, the first international conference of theatrical sound designers. She was also part of the planning and staffing committee for the Sound and Lighting Design Exposition at the 2003 and 2007 Prague Quadrennial.