Project sponsors and procurement · 7 min read
Scope creep is the uncontrolled expansion of a project's requirements after the contract is signed - and on a vendor deal it almost always arrives as a change order. What was quietly moved to a "future phase" during scoping resurfaces as a six-figure invoice. Here's how buyers prevent it.
Published 14 June 2026
Download the guide(PDF)A requirement without an acceptance test is an invitation to dispute. Define each deliverable with a testable criterion - what specifically counts as done - so "that's not what we meant" never becomes a billable change.
Make the vendor list, in writing, everything excluded from the fixed price with a dollar-impact estimate. An exclusion you've named and priced is a negotiation; an exclusion you discover mid-implementation is a change order.
Negotiate an aggregate cap on change-order value and a governance process: who approves, against what criteria, at what price. Without a cap, the fixed-fee proposal is a floor, not a ceiling.
Scope drifts between proposal revisions - a line quietly disappears, a number softens. Keep a commitment ledger comparing versions so anything dropped is caught before it becomes a gap you pay to fill later.
Ambiguity at signing. Anything left vague or moved to a "future phase" during scoping gets resolved in the vendor's favour later and billed as a change order. Locking scope with testable acceptance criteria and a registered list of priced exclusions prevents it.
Negotiate an aggregate change-order cap and a governance process before signing, register every exclusion with a dollar estimate, and track proposal versions so quietly-dropped scope is caught early.
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