Job Instruction (JI)

Introduction: JI

Job Instruction (JI) is one of the core modules of Training Within Industry (TWI), a World War II-era programme designed to quickly upskill workers. It provides a structured method for teaching employees how to perform tasks correctly, safely, and consistently. JI is still widely applied today within Lean environments to build capability, reduce variation, and support standardised work.

Background

TWI was developed in the United States during the 1940s to train large numbers of inexperienced workers for wartime production. The Job Instruction module focused on “teaching supervisors how to teach” by breaking down jobs into key steps and points of attention. After the war, TWI methods were adopted in Japan and became foundational to the Toyota Production System, influencing modern Lean practices worldwide.

Key Elements / Features

• Preparation: The trainer prepares the workplace and reviews the job breakdown sheet.
• Job Breakdown: Each task is divided into important steps (what to do), key points (how to do it), and reasons (why it matters).
• Four-Step Method:
  1. Prepare the learner – Create a supportive environment and explain the purpose.
  2. Present the operation – Demonstrate the job clearly, step by step.
  3. Try out performance – The learner practices while the trainer observes and coaches.
  4. Follow up – Check progress, reinforce correct habits, and provide feedback.
• Consistency: Ensures everyone is trained the same way, reducing variability.
• Focus on safety and quality: Embeds critical points to prevent errors and accidents.

Applications / Examples

• Manufacturing: Training operators on assembly tasks to ensure quality and safety standards.
• Healthcare: Teaching nurses consistent procedures for patient care or medication administration.
• Service industries: Standardising customer service scripts and interactions.
• Logistics: Training staff on safe and efficient handling of equipment and goods.

Relevance / Impact

Job Instruction helps organisations:

• Reduce training time for new employees.
• Increase consistency, quality, and safety.
• Build a culture of standardised work as a foundation for continuous improvement.
• Empower supervisors with effective teaching skills.

See also

• Training Within Industry (TWI)
• Job Methods (JM)
• Job Relation (JR)
• Competence Matrix