Exploring constraints in projects : a construction case study

Abstract

Theory of Constraints (TOC) suggests managing a system according to its constraints. Critical Chain Project Management (CCPM), as an application of TOC to project management, defines a project as a chain of activities with duration as its core constraint. However, the project success literature implies that projects have different characteristics and require different approaches. This study is part of broader research that attempts to re-examine CCPM assumptions and identify constraints in different types of projects.

This paper presents a case study from the construction industry. Multiple semi-structured interviews and project documents have been used as sources of data. TOC Thinking Process logic tools were used to identify the core constraint . Further investigations are made to examine other CCPM assumptions in the context of the case. CCPM assumes that projects are plagued by uncertainty, that task times are overestimated as an attempt to avoid the undesirable effects of such uncertainty (including project lateness), but that such added safety time is actually wasted. These issues, assumed by CCPM to exist, were found to exist in this case project.The CCPM’s solution requires the establishment of centralized priorities for the project and elimination of deterministic start dates. These requirements were found to be challenging in the case project.