The Lie of the Iron Triangle

In my pre-Agile career, I often had that experience of a project getting scoped, planned, budgeted, quoted, sold, and scheduled — and then almost immediately going off the rails. A late-breaking requirement or sudden new scheduling demand can turn the best laid plans of PMs and Managers into nonsense almost immediately.

Or even if that doesn’t happen, the natural course of development causes complexities to surface that couldn’t have been foreseen during planning. No amount of good intentions or hard work ever seemed to save us; we always ended up having to explain to the customer why they weren’t going to get what they paid for on the schedule we promised. ALWAYS a fun conversation.

Looking back over the waterfall phase of my career, this seemed to happen much more often than it didn’t. I can only think of two or three projects that actually went according to the plan we laid out at the kickoff meeting. And yet we kept doing it the same way, over and over! Could anything be more insane?

So you can imagine my joy when I was introduced to The Iron Triangle.

Also known as the Project Triangle or The Triple Constraint, the Iron Triangle is an attempt to convey in a simple way the interrelatedness of the aspects that impact project delivery.