The Triple Constraint Model

Posted on Mon 11 March 2019
Written by Flexi-Grant

A favourite tool that we find ourselves repeatedly coming back to is the ‘triple constraint model’.  It’s otherwise known as the project management triangle and it contends that the quality of work on any project is constrained by the project’s budget, deadlines and scope. It is up to the project manager to ensure that on any project that each of these three constraints are in balance as upset one and the others are always impacted on.  Put simply, if you want the world (scope) and you want it now (time) then you going to have to pay for it (cost)!



Why do we keep returning to the model?  Because it is a useful acid test to challenge any project on – are the 3 key constraints of scope, cost and time in balance?  Yes or no?  If you cannot say ‘yes’ immediately and without hesitation then you have work to do!  Ignore it at your peril!