Delbert Hall, Ph.D., is professor emeritus in the Department of Theatre and Dance at East Tennessee State University. Delbert is an ETCP certified rigger (Theatre) and an ETCP Recognized Trainer. He is a member of the International Alliance of Theatrical Stage Employees - Local 699. He is the co-author of several books on theatrical rigging, including: The Rigging Math Made Simple Workbook, The Arena Riggers Handbook, and The Theatre Riggers’ Handbook, with Brian Sickels. He is also the author of the PocketRigger rigging app and the originator of RigCalc.