Cas is CEO of Business Unity South Africa (BUSA) and the former Managing Director of The Banking Association SA (BASA). He is the Chairperson of the National Business Initiative. He serves on the Board of the Centre for Development & Enterprise. He is the immediate past President of the International Banking Federation (IBFed). He serves as a Council member of the University of Witwatersrand. He is also on the board of the Nepad Business Foundation. He also serves on the Steering Committee of the CEO Initiative.
Cas obtained his B. Com from the University College – Durban in 1971. He completed the Housing Finance Course with the Wharton Real Estate Centre at the University of Pennsylvania. He also completed the Effective Directors Programme with the Kagiso School of Leadership. He has contributed to numerous articles and publications on housing finance, civil society, local government and the role of civic organisations in governance