Training Within Industry (TWI): Job Instruction, Methods, Relations

By Linh Ngo · Updated Oct 13, 2026

Training Within Industry (TWI) is a set of short supervisor training programs the US government built during World War II to bring new workers up to speed fast. Its three core programs, Job Instruction, Job Methods and Job Relations, teach supervisors to train people, improve methods and handle people problems. Toyota later absorbed them into lean.

What is Training Within Industry?

Picture a plant in 1941. Experienced men have left for the military, the orders keep climbing, and the people now running the lines have never trained anyone. That was the problem TWI was built to solve. It wasn't a theory about management. It was a practical answer to one question: how do you make a supervisor good at the three things that decide whether a shop floor works?

The answer was three short courses, each taught in small groups, each built around a repeatable method. Later, a fourth piece called Program Development helped plants decide which training they needed in the first place.

Here's the short version of each program, in the words of the Lean Enterprise Institute:

• Job Instruction (JI): teaches supervisors and experienced workers how to train others, aiming for fewer defects, less scrap and fewer accidents.
• Job Methods (JM): teaches workers to improve their own methods step by step, making better use of people, machines and materials.
• Job Relations (JR): teaches supervisors to handle people problems fairly by gathering facts, weighing them, deciding, acting and checking results.

Key Facts

• TWI began inside the Council of National Defense in August 1940, and its field operations closed on September 30, 1945, according to the official 1945 TWI report.
• The same report records 1,750,650 certifications of supervisors in 16,511 plants and unions.
• Job Instruction alone reached 1,005,870 certifications by October 1, 1945, per that report's quarterly series.
• Japanese companies, Toyota among them, adopted TWI ideas after they faded in the US, per the Lean Enterprise Institute.
• Four steps run through Job Instruction: prepare the worker, present the job, try out the job, follow up.

Why TWI still matters

Most of what people call "lean" at the team level is TWI in different clothes. Standard work needs someone to teach it. Kaizen needs a method for questioning a job. A team leader needs a repeatable way to handle conflict. TWI supplies all three, and it does so for the person who actually supervises the work, not for a consultant or a manager two levels up.

It also fixes a problem that SOP libraries create. A beautifully written procedure doesn't train anyone. People learn from whoever sits next to them, and that person usually passes on their own habits, shortcuts and errors. Job Instruction replaces that drift with a short, disciplined way to teach.

The scale of the original effort tells you it wasn't a niche idea. The 1945 report counts 1,750,650 supervisor certifications across 16,511 plants and unions in about five years. Individual plants reported results too. For example, Pollak Manufacturing, which ran all three programs, reported a 20 percent reduction in break-in time for new employees, and Electric Storage Battery reported training time cut by an average of 50 percent plant-wide, both in the same report. Those are company self-reports from a wartime program, so treat them as evidence of direction rather than a guarantee you'll see the same numbers.

The three "J" programs in detail

Job Instruction: train people so the work is done right

Job Instruction is the one most teams start with. It rests on a blunt idea: if the learner hasn't learned, the instructor hasn't taught. The method has four steps.

1. Prepare the worker. Put them at ease, say what the job is, find out what they already know, and explain why it matters.
2. Present the job. Tell, show and illustrate one important step at a time, including the key points (the things that make or break the step) and the reasons behind them.
3. Try out the job. Have the learner do it and explain each step back to you. Correct errors immediately and repeat until you know they've got it.
4. Follow up. Put them on their own, tell them who to ask, check often and taper off the coaching.

Before any of this starts, the instructor builds a job breakdown sheet: the important steps, the key points for each, and the reason for each key point. That sheet is the real asset. It's essentially a one-page piece of standard work, written by the person who knows the job.

Job Methods: improve the job you're already doing

Job Methods gives a supervisor a plain way to find a better method without a redesign project. The sequence is: break down the current job, question every detail, develop the new method, and apply it. Questioning means asking who, what, where, when, why and how about each detail, then looking for steps to eliminate, combine, rearrange or simplify.

The key restriction is that you improve the method with the people and equipment you have. No capital request required. That's why it sits so close to kaizen: small, owned by the people who do the work, and repeatable.

Job Relations: lead the people side

Job Relations covers the supervisor's other half. Following the Lean Enterprise Institute summary above, the method runs: get the facts, weigh and decide, take action, and check results. It's the least glamorous of the three and often the most neglected. Yet most stalled improvement efforts fail on people problems, not technical ones: a worker who doesn't trust a change, a team leader who plays favorites, a handoff nobody owns.

Program Development: aim the training

Program Development helps a plant locate where training will pay off and plan it, so Job Instruction, Methods and Relations are applied to real production problems instead of being run as a calendar of courses. Think of it as the "where should we point this?" layer.

How TWI connects to Toyota and lean

After the war, TWI faded in the US while Japanese companies kept using and adapting it. According to the Lean Enterprise Institute, Toyota was among them. You can see the fingerprints. Job Instruction's job breakdown and key points mirror how standard work is documented and taught. Job Methods mirrors the kaizen habit of questioning every step. The "improve, then standardize, then improve again" rhythm behind PDCA runs through the whole system.

Treat the Toyota link as influence and adoption, not as a single clean handoff. Toyota built its own system, and TWI is one of its ingredients.

TWI compared with related methods

The simplest way to remember it: standard work and SOPs are documents, kaizen and PDCA are improvement loops, and TWI is how you build the people who write the documents and run the loops.

How to run Job Instruction, step by step

Here's a version you can use on your next new hire, even in an office.

1. Pick one job and one learner. Start with something repeatable and consequential: processing a refund, preparing a quote, setting up a customer account.
2. Build the breakdown sheet first. Watch an experienced person do it. Write the important steps, the key points and the reasons. Don't skip this because "everyone knows how."
3. Check the sheet with the best performer. If they'd do it differently, find out why and fix the sheet, not the person.
4. Prepare the worker. Explain the job, its purpose and where it fits, and ask what they already know.
5. Present one step at a time. Show, explain the key points and give the reasons. Don't dump the whole job at once.
6. Have them try it, then explain it back. Ask why each key point matters. If they can't say, they haven't learned it.
7. Follow up on a schedule. Check on day one, day three and week two. Walk the floor or the queue, and look at the work, using the same habits as a gemba walk.
8. Update the sheet. When the learner finds a better way, change the sheet and tell the others.

Job breakdown sheet template

Copy this into a doc or spreadsheet. One sheet per job.

Two quick rules for filling it in. A step is something that moves the work forward, not a detail. A key point is something that would hurt if missed, or makes the step easier to do right. If a "key point" can't name a reason, it's probably personal preference, so cut it.

Examples by business function

Office and service work is where TWI is most underused. People assume knowledge work can't be broken into steps. It can. The "important step" is usually a decision or a handoff, and the key points are usually the checks nobody wrote down. If your team trains by shadowing, you already have the problem Job Instruction solves.

Do's and don'ts

Do

• Train the supervisors and team leads first, since they teach everyone else.
• Write the breakdown sheet before you teach, and test it with an expert.
• Teach one step at a time and check understanding by having the learner explain it back.
• Treat the sheet as a living document and update it when a better method is proven. See process standardization for how to keep that discipline across teams.
• Pair Job Methods with a small kaizen event so improvements actually get used.

Don't

• Don't hand a new hire a long manual and call it training.
• Don't blame the learner when the learning fails. If they didn't learn, change how you taught.
• Don't write a sheet at your desk without watching the work.
• Don't cram every detail into key points. If everything is a key point, nothing is.
• Don't treat TWI as a one-off class. It sticks only when supervisors practice it on real jobs and managers check on it.

Where to start

Pick one job that new people struggle with, build a breakdown sheet with your best performer, and teach the next hire with the four steps. Then run Job Methods on the same job to see what you can cut. For the wider picture of how these pieces fit together, read about lean methodology.