Procurement & finance
Milestone Billing
Paying against defined, verifiable units of completion rather than against elapsed time or a percentage. The whole discipline lives in the definition: if two reasonable people could disagree about whether a milestone is met, it is not a milestone.
"Design 60% complete" fails the test. It is a disagreement with a payment attached. "Stage 2 package issued for review, comprising drawings X to Y at revision C" passes — something either was issued or it was not.
And this cannot be fixed later. A vague milestone written in March is argued about in September, and it is settled by whoever has more leverage — which, halfway through an engagement whose deliverables you still need, is very rarely you.