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Continuous improvement without the friction.

Twelve guided DMAIC tools, six reference guides and 21 printable cheat sheets for practitioners at every belt level. Your work saves in this browser as you go, and you can save a project file to keep or share.

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DDefine
MMeasure
AAnalyse
IImprove
CControl

Start with the tool your project needs today.

All twelve tools

D · DEFINE

Project Charter

Problem, SMART goal, scope, team and sign-off. If the Sponsor won't sign it, the project isn't ready to start.

Open Project Charter

A · ANALYSE

5 Whys

Branch from symptom to root cause on a canvas. A root cause only counts once it passes the "therefore" read-back.

Open 5 Whys

ALL PHASES

A3 Report

The whole project story on one page, from background to follow-up. Keep it current at every tollgate.

Open A3 Report

Work through DMAIC.

Pick the phase your project is in. Each phase lists its tools and the guides behind them.

01 · D

Define

Agree the problem, goal and scope.

Project Charter
SIPOC

02 · M

Measure

Establish a reliable baseline.

Data Collection Plan
Value Stream Map
Run Chart
Control Chart

03 · A

Analyse

Find and verify the root causes.

Pareto Analysis
5 Whys
Fishbone Diagram

04 · I

Improve

Test and implement countermeasures.

FMEA

05 · C

Control

Sustain the gain and hand over to the process owner.

Control Chart
Run Chart
FMEA

ACROSS EVERY PHASE A3 Report Lessons Learnt Keep the A3 current at every tollgate and capture lessons as you go, not only at close.

21 cheat sheets, ready to print.

Worked examples, decision tables, facilitation guides and tollgate checklists. Take them into the workshop.

Browse cheat sheets

Data Type	Subgroup = 1	Subgroup 2–9	Subgroup ≥10
Continuous (variable)	XmR / ImR	XbarR	XbarS
Defective (pass/fail)	—	p-chart (variable n) · np-chart (fixed n)
Defects (count)	—	c-chart (fixed area) · u-chart (variable area)

Data Type	Subgroup = 1	Subgroup 2 to 9	Subgroup 10+
Continuous (variable)	XmR / ImR	XbarR	XbarS
Defective units (pass/fail)	n/a	p-chart (variable n) or np-chart (fixed n)
Defect count	n/a	c-chart (fixed area) or u-chart (variable area)

Solution	Impact on root cause	Feasibility	Cost	Speed	Total
Solution A	5	4	3	4	16
Solution B	3	5	5	5	18
Solution C	5	2	1	2	10

Metric	Before	After	Improvement
Invoice cycle time	8 days	1.8 days	78% reduction
Late payment penalties	£15k/month	£0/month	£180k/year saved
Budget code error rate	22%	3%	86% reduction

Cause Category	Count	% of Total	Cumulative %	Priority?
Wrong budget code	84	42%	42%	✓ Vital few
Missing fields	54	27%	69%	✓ Vital few
Wrong supplier details	28	14%	83%	✓ Vital few
Duplicate submission	14	7%	90%	Trivial many
Other	20	10%	100%	Trivial many

Suppliers	Inputs	Process	Outputs	Customers
Requesting team	Purchase request form	1. Receive request	Logged request	Finance team
Finance system	Budget report	2. Validate budget	Budget confirmation	Procurement
Line manager	Approval policy	3. Approve purchase	Signed approval	Procurement
Procurement team	Vendor details	4. Raise PO	Purchase Order	Supplier, Finance
Supplier	Delivery note, Invoice	5. Confirm and close	Goods receipt, Paid invoice	Requester, Finance

Tool	Phase	Purpose	Output
Project Charter	Define	Align team on problem, goal, scope and team before work starts	Signed authorisation document
SIPOC	Define	Map the high-level process and define project boundaries	5-column process overview
Data Collection Plan	Measure	Agree what to measure, operational definitions, sample size and who collects	Signed-off plan and measurement system check
Run Chart	Measure / Control	See whether a measure has really changed over time, using the median and run rules	Time-ordered chart with signals flagged
Value Stream Map	Measure	Quantify waste in time across the full value stream	Current-state map with lead time and PCE
Check Sheet	Measure	Collect structured data on defect types, frequencies and locations	Tally data ready for Pareto analysis
Pareto Chart	Analyse	Prioritise the vital few causes driving 80% of the problem	Ranked bar chart with cumulative % line
Fishbone Diagram	Analyse	Structured brainstorm of potential causes across 6M categories	Visual cause map with prioritised causes
5 Whys	Analyse	Drill from symptom to verified root cause	Causal chain with validated root cause
Control Chart	Measure / Control	Distinguish special cause from common cause variation	Statistical process behaviour chart
FMEA	Improve / Control	Proactively identify and prioritise failure risks by RPN	Risk register with prioritised actions
A3 Report	All phases	Document the complete improvement story on one page	Single-page problem-solving document
Lessons Learnt	All phases	Capture what happened, why and what will be done differently	Structured retrospective with action log

Continuous improvement without the friction.

Start with the tool your project needs today.

Project Charter

5 Whys

A3 Report

Work through DMAIC.

Define

Measure

Analyse

Improve

Control

21 cheat sheets, ready to print.

The 8 Wastes: TIMWOODS

What Is Waste?

How to Use This Framework

In a Gemba Walk

In a VSM Session

In a DMAIC Project

Data Analysis

Pareto Analysis: The 80/20 Principle

How to Build a Pareto Chart

Control Charts: The Voice of the Process

Choosing the Right Chart

XmR Control Limit Formulas

The Nelson Rules: Signals of Special Cause

Process Capability: Cp and Cpk

Other Key Analysis Tools

Histogram

Scatter Diagram

Box Plot

Data Gathering

The Measurement Philosophy

Check Sheet

Observation Sheet

Stratification

Sampling Strategy

Voice of the Customer (VOC)

Gage R&R (MSA)

Process Mapping

Why Map Processes?

SIPOC

Standard Flowchart

Swimlane / Cross-Functional

Value Stream Map (VSM)

Spaghetti Diagram

Deployment / Matrix Map

Standard Flowchart Symbols

Value Stream Mapping

What is a Value Stream Map?

How to Build a Current State VSM

Key VSM Metrics

What is Lean Six Sigma?

The Origins

The 5 Lean Principles

The Belt Structure

5 Whys

What Is It?

Worked Example

Rules for a Valid Chain

Root Cause Validation Test

Common Mistakes

The 8 Wastes: TIMWOODS

What Is Waste?

The 8 Wastes

How to Use

Remember

A3 Report

What Is It?

The Eight Sections

Toyota's A3 Thinking Principles

Analyse Phase

Purpose

Root Cause Analysis Tools

Root Cause Validation Test

Analyse Tollgate Checklist

Project Charter

What Is It?

The Nine Sections

Common Charter Mistakes

Control Charts