Most capital projects that go badly wrong were in trouble before anyone broke ground. The scope wasn't settled, the estimate was a guess, the funding was assumed, or the team pushed into design before anyone confirmed the project was worth doing. Stage-gate governance exists to catch those problems while they're still cheap to fix, by forcing a formal decision at a handful of points where the project either earns the right to continue or doesn't.
This guide explains how stage gates work, what decision each gate should make, what documents each one needs, and the mistakes that turn gates into paperwork. It draws on two well-tested public-sector models: the Treasury Board of Canada Secretariat's gating guidance and the UK Gateway review process.
What a gate is, and what it isn't
The Treasury Board Secretariat's Guide to Project Gating describes a gate as a key decision and control point in the project life cycle, where a formal review of project health takes place. Each gate ends in a decision. The guide lists four possible outcomes: proceed, proceed with conditions, don't proceed yet (fix the gaps and come back), or terminate.
Two features make it a gate rather than a status meeting:
- Money follows the decision. The TBS guide says funds for the next set of work are released only after a positive gate decision, and that a gate must come before any decision to release funds.
- One person decides. The guide puts accountability on a single individual, such as the project sponsor or the chair of an investment board, who must seek and consider the views of key stakeholders before deciding.
Termination has to be a real option. If the only possible outcome is "proceed", the gate is a ceremony. The point is to give leadership a structured chance to stop, reshape or delay a project before the next tranche of money is committed.
Gates and reviews are different things
Owners often blur two ideas that the public-sector models keep separate.
A gate is a decision by the organization. A gateway review is an independent assessment that informs that decision. The UK's Gateway process, now run by the Infrastructure and Projects Authority, uses short, independent peer reviews commissioned by the Senior Responsible Owner. Queensland Treasury's version of the process describes review teams of three or four people from outside the project, reviews that normally take three to five days, and a confidential report to the project owner with a delivery confidence rating on a five-point scale from green to red.
The distinction matters because a good review doesn't remove the need for a decision. A review can rate a project amber-red and the sponsor can still choose to proceed, with conditions. What a review does is make sure the decision-maker has heard an independent view before committing the next tranche of money.
A six-gate model for building projects
The TBS guide doesn't require a fixed number of gates, but its sample model uses six, numbered 0 to 5. The UK Gateway reviews follow a similar arc: strategic assessment, business justification, delivery strategy, investment decision, readiness for service, and operations review and benefits realisation. Adapted for a commercial, retail or institutional building project, the model looks like this.
View the data
| Gate | Decision |
|---|---|
| Gate 0 | Confirm the need |
| Gate 1 | Business case and options |
| Gate 2 | Option and delivery plan |
| Gate 3 | Investment decision |
| Gate 4 | Readiness for service |
| Gate 5 | Close and benefits |
Gate 0: Confirm the need
Is there a real business problem or opportunity, and is it worth spending money to study? This gate approves a modest feasibility budget, nothing more. The question isn't "how do we build it?" but "should we look at this at all?"
Gate 1: Business justification and options
Does the business case hold up, and which options deserve detailed study? Options should include doing nothing, leasing, renovating and building new where those are realistic. The TBS sample gate narrows the field to a short list. Feasibility design and an early-stage estimate support it.
Gate 2: Preferred option and delivery strategy
This is where the organization picks one option and decides how to deliver it: delivery model, procurement approach, contract form and key risks. Schematic design, a firmer estimate, a risk register and a draft master schedule support it. Delivery strategy decisions are hard to reverse once tendering starts, so this gate deserves more scrutiny than it usually gets.
Gate 3: Investment decision
The big one. The TBS model calls it the decision to fund the project deliverables; the UK model calls it the investment decision. For a building project it usually sits just before contract award, when tender prices or a negotiated price are known. After this gate, the owner is committed to a contract and stopping becomes expensive. Everything the board needs to know should be on the table here: confirmed cost with contingency, schedule with risk analysis, funding source, and the contract terms.
Gate 4: Readiness for service
Is the building ready to hand over and operate? This gate checks commissioning results, deficiency status, operations staffing and training, permits and occupancy approvals, and the tenant or user move-in plan. Rushing it is how owners end up occupying a building whose systems haven't been proven.
Gate 5: Close and benefits review
Did the project deliver what the business case promised? This gate confirms close-out is complete, financial accounts are settled, and lessons learned have been captured. The UK model repeats benefits reviews over the life of the asset, which is worth copying for owners with portfolios.
What each gate needs to see
Gates fail most often because the decision-maker is asked to approve without the right evidence. Each gate should have a defined package of documents, agreed in advance, so the team knows what "ready" means.
View the data
| Gate | Decision | Evidence the decision-maker needs |
|---|---|---|
| Gate 0 Confirm the need | Is the problem worth studying? Fund feasibility. | Problem statement, strategic fit, rough order-of-magnitude cost range |
| Gate 1 Business case and options | Is the case sound? Which options go forward? | Options incl. do-nothing and lease, early estimate range, key risks |
| Gate 2 Option and delivery plan | Approve preferred option and delivery model | Schematic design, OPR, firmer estimate, risk register, schedule, procurement plan |
| Gate 3 Investment decision | Commit funds and award the contract | Tender or negotiated price, contingency, risk-based schedule, funding, contract terms |
| Gate 4 Readiness for service | Accept the building and start operations | Commissioning results, deficiency list, occupancy permits, O&M staff and training |
| Gate 5 Close and benefits | Confirm close-out and benefits | Final account, closeout documents, lessons learned, benefits review |
Two principles keep the package useful. First, the evidence should get firmer at each gate. An estimate at Gate 1 is a range; at Gate 3 it should be a committed price plus contingency. A schedule at Gate 1 is a few milestones; at Gate 3 it should be a baseline-ready schedule. Second, the package should be short. A board member should be able to read the decision memo in ten minutes and find the supporting material if they want it.
Where stage-gate governance goes wrong
On programs we've supported, gates usually fail in one of these ways:
- The gate is scheduled, not earned. The meeting happens on a fixed date whether or not the evidence is ready, and the team presents what it has. Gates should be triggered by readiness, with the schedule allowing time for a "not yet" outcome.
- Work runs ahead of the gate. Design or procurement continues at full speed while the gate decision is pending, so the decision is made under pressure from sunk cost. If early work must continue, approve a limited, named scope for it.
- Conditions aren't tracked. "Proceed with conditions" is approved, and nobody checks whether the conditions were met. Each condition needs an owner and a due date, reviewed at the next gate.
- Too many gates. A small fit-out doesn't need six gates. The TBS guide doesn't fix the number of gates and allows more than one gating model. Combine gates for small or repeat projects; keep the full set for large or unusual ones.
- No one is accountable. A committee "approves", but no named person owns the decision. When the project later struggles, nobody can say who decided what, on what evidence. Our post on RACI for the owner-side team covers how to fix that.
Plan the gates at the start
The TBS guide recommends setting up a gating plan at the start of the project, no later than business case approval, and reconfirming it at each gate. For an owner, a gating plan is a one-page document that lists the gates, who decides at each, what evidence is required, whether an independent review is needed, and the target dates. It should sit alongside the project charter and the master schedule.
Build the gate decision dates into the schedule as milestones, with realistic durations for preparing the package, reviewing it and making the decision. Board meeting calendars matter here. A gate that misses a quarterly board meeting can cost months, and that delay should be visible in the schedule from day one, not discovered later.
What owners should do
- Write a one-page gating plan before the business case is approved: gates, decision-makers, required evidence and target dates.
- Name one accountable decision-maker per gate, and make sure they understand that termination and "not yet" are valid outcomes.
- Tie funding releases to gate decisions. No commitment of the next phase's money until the gate is passed.
- Use independent reviews for large or high-risk projects, especially before the delivery strategy and investment decisions.
- Track conditions. Every "proceed with conditions" gets a list of conditions with owners and due dates, checked at the next gate.
- Scale the model. Use the full set of gates for major projects and a lighter version for small or repeat work.
The bottom line
Stage gates are only as good as the decisions they force. A gate with clear evidence requirements, one accountable decision-maker and real authority to stop the project is one of the best controls an owner has. A gate that always says "proceed" is just a meeting. The cheapest time to cancel or reshape a project is at Gate 1 or Gate 2, so that's where owners should look hardest.
Want an independent review before your next gate decision? Book a 30-minute call with Benjamin R. Consulting.
Sources: Treasury Board of Canada Secretariat, Guide to Project Gating (2021); UK Infrastructure and Projects Authority, Gateway Review 1: Business Justification (2021); Designing Buildings Wiki, OGC Gateway Review 5; Queensland Treasury, Gateway Review Guidebook (2020). The six-gate building model is an adaptation by Benjamin R. Consulting. This article is general information, not financial or legal advice.