The Paradigm of the Iron Triangle

Background and Originality: The project triangle, also named as the triple constraint, iron triangle, golden triangle, and agile triangle, is a central concept in project management research and practice that represents the relationship between key performance measures. However, there is disagreement about which criteria should be represented at the vertices of this triangle. The purpose of this paper is to explore which concepts are part of the project triangle and how these concepts have changed over time. Our purpose is to conduct a systematic review of scientific articles dealing with the topic of the project triangle and its elements (time, cost and scope). We want to demonstrate that there is a theoretical gap in the classical theory of the project triangle and that the elements of the project triangle are ultimately reflected in successful project management. Addressing this topic will contribute to eliminating or at least reducing the perceived theoretical research gap, or confusion regarding the positioning of the elements of the project triangle and the connection of these elements to the success of projects. Method: A systematic review of the scientific literature will be conducted using publicly available databases, namely "iron triangle", "triple constraint”, “project performance" and "success factors" as search terms. Scientific articles and doctoral/master's theses were searched in the databases Academia.edu, ProQuest, ScienceDirect, Elsevier/Scopus and Google Scholar. We excluded literature that does not directly relate to the field of research. Results: We found out that there is a gap in the basic theory of the project triangle or to be more exact confusion about the positioning of quality and scope of the project in the project triangle. We therefore want to reduce the gap and confirm the thesis that quality is not one of the 3 elements of the project triangle, but is indirectly defined through the elements of the project triangle (time, cost, scope). The authors of the research carried out so far listed the elements of the project triangle and defined success criteria of the projects by group, among which the individual elements of the project triangle were classified. We expect to confirm the hypothesis that there is a connection between the elements of the project triangle and success of projects. Society: Our research will confirm the dimensions of the project triangle concept and show the influence of its elements on the most common groups of success criteria, with the help of which companies measure the success of projects. This research will show which elements of the project triangle and criteria are given greater importance by the scientific literature, which represents a starting point for optimization in the field of managing various types of projects. Understanding the concept of the project triangle and its role in the creation of success criteria will help the various stakeholders involved in project management to be more motivated to monitor the elements of the project triangle and that this will allow them to manage more effectively, which in turn also affects their commitment in performing project duties. Limitations / further research: The topic under discussion has been well studied for the past 20 years, although it has undergone a great deal of theoretical transformation. At the same time, we note that the theoretical treatment is not followed by scientific research, as it mainly covers the field of methodology, factors and strategies for the success of project management in the construction industry or on large investment projects, in the field of IT and healthcare. Proposals for further research will be made in order to conduct research on this topic in other industries and on other types of projects and on several different stakeholders and/or stakeholder groups involved in project management.