The classic project management triangle can be used by all managers to help understand some of the difficulties of implementing change and the complexities of project management.
All projects have constraints, those things that restrict the decisions that can be made – for example, most projects have a cost constraint as there will only be a certain budget available to the project (and the organisation). A project manager must work out how to deliver a project given all the constraints and this can be difficult as there are always many constraints. One approach is that of the project management triangle, which identifies three constraints that will apply to all projects and that affect each other; tightening one constraint will allow some flexibility in the others and flexibility in one area will affect the others.
The three constraints in the project management triangle are time, cost and scope.
Time Constraint
Most projects have an absolute deadline which cannot be missed without severe detriment to the organisation. This is different from the completion deadline for the project – for example, in the late 1990s ‘the year 2000 problem’ had a deadline, midnight on 31 December 1999 but most Y2K projects had project deadlines much earlier than that.
All the activities in a project take time and every activity can take a shorter or longer amount of time depending on factors such as the experience of the personnel completing the task, the number of people working on the task and when the task can be completed (for example some tasks can only be completed at an organisation’s month end).
Time is the most difficult constraint to control in a project as deadlines are usually set to ensure efficient working and often the required resources are not available when needed.
Cost Constraint
All projects have finite resources available usually measured in terms of cost. There will be an agreed budget and the project manager must decide how to spend the budget on the resources needed to complete the project.
Reducing the cost of a project will have an impact on the time the project will take and changing the time available to a project will impact the cost of the project.
Project Scope Constraint
The project scope defines what will be delivered by the project. It is the list of deliverables, not to be confused with the activities to be undertaken to deliver the project. One of the jobs of the project manager is to manage the scope of a project as any change in scope will impact both cost and time.
If more items are added to the scope then both time and cost may rise, but even a subtle change to the scope can have noticeable impacts, which is why change control is vital to project success.
Project Quality
Sometimes the project management triangle is described with the three constraints time, cost and quality rather than scope, as higher quality in a project can easily lead to higher cost and sometimes more time. However, quality can also be seen as part of the scope of a project, as well defined deliverables will include a statement of the desired quality.
An understanding of the constraints in the project management triangle (cost, time and scope) can help all managers to implement change in business.
Dawn Brewer - I have a portfolio career - as a writer, management consultant, instructor and coach - after twenty years in the corporate world. My ...
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