Triple Constraints of Project Management


The achievement of an organization’s set goals and objectives highly depend on the strategies that the organization adopts in ensuring that its operations are smooth and in line with the business objectives (Haughey 1). One of the suitable strategies that businesses ought to put a lot of consideration is the aspect of project management. The success of any project depends on how best the project is organized and the organization’s readiness to manage any risks and constraints that might interfere with the goals and objectives of the given organization. However, different projects are affected by several constraints. Some of the notable project management constraints include quality, time and cost. This paper provides an overview of the project management triple constraints, cost-quality tradeoff, cost estimating and project control, and the general evolution of project constraint.

Understanding the project management triple constraint

Any given project is affected by challenges related to scope, time and cost (Haughey 1). The combination of these three elements forms the triple constraint, which can be represented in a triangle as shown below.

Showing Project Management Triple Constraint
Figure 1: Showing Project Management Triple Constraint

From the representation above, it can be seen that when all the other aspects of the project management are fulfilled, the end result is a quality project. As such, the time, scope and cost of any project must be managed together to ensure that the final results are as expected and that they satisfy the objectives of the project. For this reason, a project should be completed within the stipulated cost, scope, on time and should meet the organization’s goals and customer demands.

However, over time the project management triple constraint has evolved to put into emphasis customer expectations, as shown in the diagram below.

Showing the evolution of triple constraint
Figure 2: Showing the evolution of triple constraint

The inclusion of ‘quality’ to the three elements of project management (time, scope, and cost), and the change of focus to customer’s expectations ensures that any project focuses on the expectations of a specific customer due to the fact that different customers have different needs and demands that ought to be met.

Triple Constraints of Projects: Quality, Cost, Time

The primary aim of any project manager is to ensure that their project succeeds amidst the triple constraint (time, cost and quality) (“Enterprise: Triple constraints of projects’’ par.1). The quality needed in any project determines its scope, while the resources to be used dictate the overall cost of the project. On the other hand, the time limit determines the schedule within which the project must be completed. The quality, time and cost of any project are mutually related; implying that the restriction or extension of any of these elements interferes with the state of the other two elements of the project management process (Haughey 1). As such, a project can only be successful if the three elements are planned, resourced and executed effectively because the scope, schedule, and cost of any project are the primary factors considered to determine whether or not a project has been successful.


Any project must have a scope, which refers to the degree of project’s coverage. Thus, for effective project management, the scope of the project must be clear and specific to ensure that the project is easy to understand in terms of what to be achieved. For this reason, the scope ought to outline expressly the content of the project, data, features, and functions, among other necessary factors for the project’s success (“Enterprise: Triple constraints of projects’’ par.3). Generally, the scope of any project is used in expressing the expected outcome of a project.


Resources or cost is the second element to be considered for effective project planning in any organization. For any resources to be used in a project, some amount of cost must be incurred, which implies that cost and resources are interchangeable when it comes to aspects of project management. As such, the cost of any project refers to any resources that are needed in a given project to ensure effective and reliable results. For this reason, the cost in project management can include resources such as effort, materials bills, contractors’ rates, and labor, among other factors that are needed to ensure that the project is driven towards achieving the set goals and objectives.


When carrying out a certain project it is important to analyze the time needed for the completion of the project. Such analysis is necessary since it highlights the time needed to finish all the components of the entire project. In addition, analyzing the project’s time ensures that the available time for the entire project is allocated to a specific task. As such, effective planning of time in project management ensures that the project is completed within the stipulated time.

The triple Constraints in Project Management

The triple constraints outlined above are very important in project management. Often, managers ought to deal with any challenges that they come across in the course of any project. However, the success of any project starts by balancing the three constraints. One of the major causes of project failure is the sudden change of the project’s scope, time and initial cost. Changing any of the three constraints interferes with the overall project, and the quality of its outcome. For example, any given project ought to have a certain budget, and might be adversely affected upon the reduction or increase of the project’s time or scope. In the UAE, a lot of changes are expected by the year 2020, such as the construction of the Dubai Canal and the Expo site. However, given the size of the projects, and a tight schedule of 2020, a lot of money will be needed to ensure that all the planned projects are completed by the set date.

Cost Quality Trade-Off

In project management, there are decisions that require the project manager to consider balancing several aspects of the project in order to ensure that the set objectives are achieved, or perhaps to forego a given outcome, though it might be desirable, in favor of another outcome that eventually maximizes the involved outcomes. As such, for any effective cost-quality trade-off in a given project, the project manager is required to understand the triple constraint, as well as any other consequences that might result from the adjustment of the key elements of project management constraints (El-Rayes and Kandil 477). Such knowledge ensures effective planning, analysis and protection of the project against unexpected risks, as well as unforeseen client expectations. However, whenever needed, it is important to forego some cost for a case whereby the returns are worth (Pour, Modarres and Tavakkoli-Moghaddam 404). However, before applying any form of trade-off, it is important to understand the consequences of such actions on the project’s process and outcome. A good example is a case in Dubai. The cost to be incurred in infrastructural development is high, while the returns are valuable.

Cost Estimating and Project Control

The primary goal of any project is to ensure that customer requirement and the organization’s goals are achieved (Catania, Armstrong and Tucker 23). However, this cannot only be achieved if all the constraints are balanced and managed as expected. Therefore, it is important for the project managers to ensure that they effectively estimate any cost, and align it with other constraints such as project’s time and scope. To ensure effective cost estimation and project control, it is important for the project manager to put into consideration several factors. It is important to avoid planning approval processes that are inappropriate, ensure that the available amount of money is planned for projects that gains value for the invested money in the long run. Also they should have a given programme approach (“Project cost estimation and control” par. 1).

To ensure that an organization maintains an improved cost estimation during projects, the project manager should ensure that they have preliminary estimates with respect to the scope that is yet to be finalized. However, such estimates do not qualify as official estimates until the project’s scope has been finalized. In addition, it is important to ensure that all the necessary costs for any given project are factored in the project’s estimates. Secondly, the scope of any project is very instrumental in determining the outcome of the concerned project (Abeyasinghe, Greenwood and Johansen 45). As such, during the feasibility stages of a project, the project manager should ensure that they have a clear scope, as well as have a suitable schedule for the project. This ensures that any necessary changes on the scope of the project or its schedule are implemented with ease.

The other factor to consider when planning the development of a project is the availability of risk assessment measures and control. Often, it is hard to carry out a project without being subjected to several risks. For this reason, having suitable measures to assess, prevent as well as mitigate project’s risks can be a suitable way to ensure that the project is successful. However, project managers should determine the different risks in any given project, categorize them based on their seriousness, and mitigate or monitor them. In addition, all costs involved in risk assessment and control should be estimated beforehand to avoid inconveniences in the course of the project.

Evidently, for cost control improvement, the project manager should ensure that all involved stakeholders are aware of their role and that they are competent for the tasks assigned. Secondly, all necessary resources should be available, along with comprehensive systems to effectively manage the given project (Abeyasinghe, Greenwood and Johansen 29). In addition, the necessary measures ought to be put in place to minimize cases of project risks and other unknowns.

Evolution of the Project Constraint

The traditional overview of project constraint focused on three primary elements; scope, time and cost, which were used in the construction of a triangle showing how these three elements interrelated (see figure 1 above). Due to the mutual relationship between these three factors, a shift of one of the factors during project management necessitates manipulation of the remaining two elements.

Even though the Triangle Model consistently represented cost and time as elements of project management, the element of scope has been used interchangeably with quality, deliverable, product or even goal. Such a representation of scope with varying elements presents a scenario that can have diverse impetus on the other elements, as well as on the entire project’s process and output. Thus, in order to deal with the blurred focus of the Triangle Model, quality was included as a primary element of project management, thereby changing the Triangle Model to Diamond Model. In spite of the fact that the addition of quality as a primary constraint of project management is merited, this approach still does not address with clarity project’s process and its output (Catanio, Armstrong and Tucker 23). In addition, the Diamond Model fails to depict a clear relationship between all the key constraints of project management.

Following the failure of the Diamond Model and the blurredness of the Triangle Model of project management constraints, a more recent model has evolved whose approach takes into consideration six elements to monitor and manage. This model considers the approach of two overlaid triangles, but highlights the link, as well as the difference between input and output factors of each of the two triangles (Abeyasinghe, Greenwood and Johansen 45). This model brings together scope, cost and time in one triangle and risk, quality and resources on another triangle, to capture all aspects involved in project management.


From the discussion above, it can be seen that effective management of any project is very important since it determines whether or not the organization’s goals and objectives as well as the demands of the customer are met. However, project management faces a number of constraints such as cost, time, and quality. For this reason, the management of any organization should ensure that the necessary measures are set to effective manage a given project. This can be done by ensuring that there is a balance between all the project’s key constraints.

Works Cited

Abeyasinghe, Chelaka, David Greenwood and Eric Johansen. ‘An efficient method for scheduling construction projects with resource constraints.’ International Journal of Project Management 19.1 (2001): 29-45.

Catanio, Joseph, Gary Armstrong and Joanne Tucker. ‘Project management certification and experience: The impact on the triple constraint.’ Journal of Advances in Information Technology 4.1 (2013): 1-24.

El-Rayes, Khaled and Amr Kandil. ‘Time-cost-quality trade-off analysis for highway construction’. Journal of Construction Engineering and Management 131.4 (2005): 477-486.

Enterprise: Triple constraints of projects: quality, cost & schedule 2015. Web.

Haughey, Duncan 2011. Understanding the project management triple constraint. Project Smart. Web.

Pour, Nasser Shahsavari, Mohammad Modarres, and Reza Tavakkoli-Moghaddam. “Time-Cost-Quality Trade-off in Project Scheduling with Linguistic Variables.” World Applied Sciences Journal 18.3 (2012): 404-413.

Project cost estimation and control 2015. Web.