45 December 2005 Vol. 17 No. 4 Engineering Management Journal Critical Chain: A New Project Management Paradigm or Old Wine in New Bottles? Thomas G. Lechler, Stevens Institute of Technology Boaz Ronen, Tel Aviv University Edward A. Stohr, Stevens Institute of Technology E ver since Goldratt introduced critical chain (CC) in his book of the same name in 1997, the concept has been widely discussed in the project management literature and project management community. Some authors see CC as the most important breakthrough for project management since the introduction of the critical path method and refer to CC as the direction for project management in the 21st century (Steyn, 2002; Newbold, 1998). Others question its innovativeness and argue that it consists of known concepts presented in a different way (Maylor, 2000; Raz et al., 2003; McKay and Morton, 1998). In the last few years, several books have been published explaining the concepts underlying CC (Newbold, 1998; Leach, 2000) and a number of software packages based on CC scheduling concepts have been developed (Prochain, 1999; Scitor, 2000). Many examples of successful applications of CC have been cited in the literature (Leach, 1999) and on websites (Product Development Institute, 2005). A number of researchers have discussed the concepts underlying CC and the differences between CC and CP at a conceptual level (Raz et al., 2003; Globerson, 2000). Other researchers have focused on the technical aspects of CC scheduling using simulation analyses (Herroelen and Leus, 2001; Cohen et al., 2004). Although these studies are helpful, we share the view of Herroelen and Leus (2001 and 2002) that the discussions on both sides of the CC debate are often too general to offer guidance on CC’s advantages and disadvantages relative to established CP About the Authors Thomas G. Lechler is associate professor at the Wesley J. Howe School, Stevens Institute of Technology. His research focuses on the early development stages of new ventures and the success factors of project management to understand the dynamics and interactions between decisions, structures, and behaviors on innovation success. He has published articles in leading international and German journals and authored two books in the fields of project management and entrepreneurship and reviews regularly for several technology and innovation management journals. He holds a PhD from the University of Karlsruhe, Germany. Edward A. Stohr is associate dean for research at the Wesley J. Howe School, Stevens Institute of Technology. Prior to joining Stevens, Professor Stohr was a faculty member at NYU’s Stern School of Business for more than 20 years. His research focuses on the problems of developing computer systems to support work and decision-making in organizations. He has published articles in many leading journals. He is the co-editor of three books in the field of information systems and is on the editorial boards of a number of leading journals. He holds a PhD from the University of California, Berkeley. Boaz Ronen is a professor of technology management and information systems in Tel Aviv University, the Leon Recanati Graduate School of Business Administration. He holds a BSc in electronics engineering from the Technion, Haifa, Israel, and an MSc and PhD in business administration from Tel Aviv University, Faculty of Management. His main areas of interest are focused on increasing shareholders’ value and the application of focused management techniques and philosophies. He has published more than 100 papers in leading academic and professional journals, and co-authored a book on Value Creation, Managerial Decision Making and Cost Accounting. Contact: Thomas G. Lechler, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030; phone: 201-216-8174; fax: 201-216-5385; tlechler@stevens.edu Refereed management tool manuscript. Accepted by Special Issue Editor. Abstract: In this paper we analyze the Critical Chain (CC) approach to managing projects. Is CC as some authors assert, one of the most important breakthrough for project management since the introduction of the Critical Path concept (CP) or does CC merely consist of known concepts presented in a different way? Our discourse compares systematically CC and CPM on three conceptual levels to reveal the differences between the two approaches. We conclude that the philosophy behind the CP and CC approaches is remarkably different resulting in a different mindset for managers and a different set of management practices. The main difference is the application of the Theory of Constraints (TOC) in the CC case. As a result, CC focuses at improving the systems performance by laying out specific policies many of which are focused on resource management especially in multiproject environments that are not explicitly addressed by CP. We conclude that while the application of CC is complex, many of its ideas can be easily adapted by practicing managers. Keywords: Critical Chain, Theory of Constraints, Buffer Management, Critical Path Method EMJ Focus Areas: Program & Project Management