A3 Project Charter Template: Lean Problem-Solving on One Page (2026)

Why the A3 Constraint Matters

The A3 is named after the ISO paper size (297 by 420 mm) used to print the document. Toyota engineers in the 1970s settled on A3 because that was the largest sheet that fit through a standard fax machine, which meant problem analyses could be shared across plants without splitting onto multiple pages. The format constraint became the principle. The Lean Enterprise Institute defines an A3 as "the standard process by which Toyota and other Lean organisations identify, frame, and then act on problems and challenges".

In Lean Six Sigma the A3 is the deliverable for the Define and Measure phases of DMAIC, and often the deliverable for the entire project if the scope is small enough. In Lean manufacturing organisations it replaces the project charter outright for problems under a discretionary threshold. Compared to a PMBOK charter (3 to 5 pages) or a PRINCE2 PID (15 to 50 pages), the A3 forces a discipline most other charter formats do not: one page or it does not ship.

The Seven A3 Sections

Background

Why this problem matters to the business. Strategic context, the customer impact, and the cost of inaction.

Word budget: 60 to 100 words

Current State

What is happening today, with measured data. Not anecdotes, not opinions, just the numbers.

Word budget: 80 to 120 words plus a chart

Goal / Target State

The measurable outcome the project will achieve, with a deadline. Format: from X to Y by date Z.

Word budget: 30 to 50 words

Root Cause Analysis

Why the current state exists. The 5 Whys, fishbone, or Pareto analysis condensed to its conclusion.

Word budget: 60 to 100 words plus a diagram

Countermeasures

What the team will do to address each root cause. Specific actions, not generic improvements.

Word budget: 80 to 120 words

Implementation Plan

Owners, timelines, and dependencies. A Gantt or table, not prose.

Word budget: Visual plus 30 to 50 words of caveats

Follow-up / Confirmation

How and when the team will measure whether the countermeasures worked, plus what to do if they did not.

Word budget: 40 to 60 words

Filled A3: Bristol DC Cycle-Time Reduction

Problem statement (the "owner" line at the top of a real A3):

Order-to-shipment cycle time at the Bristol distribution centre averaged 47 hours in Q1 2026 against a customer-promised SLA of 36 hours. The breach drives a 14% same-day-shipment surcharge from the largest customer (annual exposure: GBP 480K) and a 7-point drop in CSAT.

1. Background

Order-to-shipment SLA breaches at Bristol DC. Largest customer applies surcharge; CSAT down 7 points.

2. Current State

Cycle: 47 hours mean. Wave release 18h + pick/pack 14h + carrier wait 15h. Up from 33h in Q4 2024.

3. Target / Goal

32 hours mean, 48h P95, by 30 September 2026.

4. Root Cause

Twice-per-shift wave release. 1.8 km picker walk. Single dock + carrier arrival cluster.

5. Countermeasures

Continuous wave release. SKU slot velocity audit + relocation. Carrier arrival stagger contract.

6. Plan

Wave release: 1 Jul. Slotting: 31 Jul. Carrier contracts: 15 Aug. Confirmation gate: 15 Sep.

7. Follow-Up

Daily SQL pull, weekly Gemba, escalation if not at 36h by 15 Sep.

Expanded: Current State

Metric: Cycle time (order placed to carrier handover): 47.2 hours mean, 68 hours P95

Components: Pick wave release: 18 hours. Pick + pack: 14 hours. Carrier wait: 15 hours.

Trend: Cycle time has grown from 33 hours (Q4 2024) to 47 hours (Q1 2026), a 42% increase. Order volume grew 28% in the same period; staffing grew 4%.

Expanded: Root Causes

Pick wave released only twice per shift, accumulating up to 4 hours of orders before pickers start.
Pickers walk an average 1.8 km per wave because high-velocity SKUs are stored across 3 separated zones.
Carrier handover relies on one inbound dock; queue forms after 16:00 because all carriers arrive in a 2-hour window.

Expanded: Countermeasures

Move pick wave release to continuous (every 30 minutes) using existing WMS scheduler. Owner: Operations Manager. Target: live by 1 July 2026.
Slot-velocity audit and SKU relocation. Move top 200 SKUs by line count to a single contiguous zone. Owner: Slotting Lead. Target: complete by 31 July 2026.
Stagger carrier arrival windows: contract addendum with three largest carriers to spread arrival across 5 hours (14:00-19:00). Owner: Logistics Manager. Target: contracts amended by 15 August 2026.

Expanded: Follow-Up

Daily SQL pull of cycle-time metric from WMS, published to ops dashboard.
Weekly Gemba walk by Operations Manager to validate WMS data against floor reality.
Confirmation gate: if cycle time has not reached 36 hours mean by 15 September, escalate to plant manager and re-A3.

When to Use an A3 Instead of a Full Charter

Situation	A3 fits?	Why
Operational problem under USD 100K	Yes	Team has authority. A3 is the full charter.
Cross-department initiative	Maybe	Use A3 plus a 1-page sponsorship cover.
Multi-quarter capital project	No	A3 cannot carry the budget and risk content needed.
Regulated industry capex	No	Audit trail requires a fuller charter format.
Six Sigma DMAIC project	Yes	A3 is the Define and Measure deliverable.

Frequently Asked Questions

Why is it called an A3?

It is named after the paper size. Toyota engineers wrote problem-solving reports on A3 sheets (297 by 420 mm) because that was the largest single sheet that fit through a standard fax machine in 1970s Japan. The format constraint became the principle: if you cannot fit the entire analysis on one A3, you have not understood the problem well enough. The Lean Enterprise Institute calls this the constraint that forces clarity.

How does an A3 differ from a PMBOK charter?

An A3 is a problem-solving artefact, not an authorising one. It assumes the project has already been authorised by the team's manager. A PMBOK charter is an authorising artefact: it grants the PM authority to spend money and assemble a team. In a mature Lean organisation the A3 is the work; the authorisation is informal because the team has authority to address its own problems within its line of business. In a hybrid environment, organisations sometimes use an A3 as the entire charter for problems under a financial threshold (often USD 50K to 100K).

Who writes an A3?

The person closest to the problem, typically the team leader or first-line supervisor. The owner of the A3 is the owner of the problem. A senior manager who writes A3s for their teams is breaking the model: the value of the A3 is in the thinking it forces on the author, not in the document itself. Most Toyota-trained Lean coaches treat A3 authorship as a leadership development tool.

Can A3 thinking be done digitally?

Yes, but the constraint matters. If the digital A3 scrolls, it is not an A3 anymore. Tools like Lucid, Miro, or the Toyota-published A3 templates in PowerPoint preserve the single-page discipline. The most common digital failure mode is loosening the page constraint, after which the analysis becomes a 12-page report and loses the clarity benefit.

What is the difference between A3 and DMAIC?

A3 is the document; DMAIC (Define, Measure, Analyse, Improve, Control) is the methodology. A Six Sigma DMAIC project will produce an A3 (or a series of A3s) as its outputs. The seven A3 sections map roughly to DMAIC: Background and Current State to Define and Measure, Root Cause to Analyse, Countermeasures and Plan to Improve, and Follow-up to Control.

Where can I learn more about A3 thinking?

The Lean Enterprise Institute (LEI) is the canonical English-language source, founded by James Womack. John Shook's 'Managing to Learn' (LEI, 2008) is the most-cited practical guide and walks through worked A3 examples from Toyota. Jeffrey Liker's 'The Toyota Way' covers the broader management system in which A3s sit. Both are widely used in Lean training programmes globally.

Related on this site

Six Sigma DMAIC charter Manufacturing project charter One-page charter template (non-Lean)Scope boundaries guide SMART criteria builder PMBOK charter format (for comparison)