76 Int. J. Services Operations and Informatics, Vol. 4, No. 1, 2009 Copyright © 2009 Inderscience Enterprises Ltd. Performance modelling of service businesses Barbara Jones and Ying Tat Leung* IBM Research Division, Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA E-mail: bajones@almaden.ibm.com E-mail: ytl@us.ibm.com *Corresponding author Suresh Muthulingam UCLA Anderson School of Management, PO Box 951481, Los Angeles, CA 90095, USA E-mail: suresh.muthulingam.2010@anderson.ucla.edu Sunil Noronha Yahoo! Inc., 2821 Mission College Boulevard, Santa Clara, CA 95054, USA E-mail: noronha@yahoo-inc.com Jorge Sanz IBM Research Division, Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA E-mail: jorges@us.ibm.com Abstract: Business performance continues to be one of the principal subjects in enterprise operations. The evolution of the service economy brings renewed interest to the field of performance modelling. Senior managerial decision makers constantly seek to improve the performance of an organisation. Key areas of interest are what aspects of the business are important for successful performance, and how best to control them, e.g. what investments, resource allocations and other actions must they take to maximise business performance. Our ultimate goal is to develop quantitative models and associated methods or tools that will help high-level managers of services businesses improve their performance. We believe that most organisations could improve their understanding of what drives their performance by following a more rigorous methodology. In this paper, we explore the