Gina Barney is principal of Gina Barney Associates. Through her 50 years of experience in practice, research, and lecturing in vertical transportation and control systems, she has had a profound influence on this field. Her involvement continues with her activities with the BSI Committees on Lifts, Escalators & Moving Walks, the CIBSE Lifts Group Executive Committee and as English Editor of Elevatori (the European lift magazine). Lutfi Al-Sharif is an Associate Professor at The University of Jordan. He has 30 years of experience in the area of lifts and escalators, including working for a manufacturer (Jordan Lift & Crane), for a client (London Underground), for a consultancy (WSP and Al-Sharif VTC) and in academia (The University of Jordan). He has over 20 papers published in peer-reviewed journals, is co-author of three patents and is a member of the scientific committee of the Lift Symposium held annually at the University of Northampton.