Ishikawa Diagram: What It Is, Common Uses and How To Create One

Article Summary

The Ishikawa diagram, also known as the fishbone diagram or cause-and-effect diagram, is a powerful tool used in problem-solving and quality management.

It provides a structured approach to identify and analyze the root causes of a problem or an effect.

This article explores what an Ishikawa diagram is, its common uses across various industries, and provides a step-by-step guide on how to create one.

Understanding and utilizing this tool can greatly enhance problem-solving efforts and drive continuous improvement in any organization.


In today’s dynamic and complex business environment, organizations face various challenges and problems that require effective problem-solving techniques.

The Ishikawa diagram, developed by Dr. Kaoru Ishikawa, is a visual tool that aids in identifying and analyzing the root causes of a problem or an effect.

Commonly known as the fishbone diagram due to its shape, this tool provides a structured approach to problem-solving and quality management.

This article delves into the concept of Ishikawa diagrams, explores their common applications across different industries, and provides a comprehensive guide on creating one.

Types of Ishikawa diagrams

The different types of Ishikawa diagrams include:

  • The 6Ms Ishikawa diagram:
    The 6M diagram organizes information into six categories: man, machine, material, method, mother nature, and measurement.It is most commonly used in the manufacturing industry.
    For instance, it could be used to identify bottlenecks slowing down the manufacturing process in a candle business.
  • The 8Ps Ishikawa diagram:
    The 8P diagram organizes information into eight categories: procedures, policies, place, product, people, processes, price, and promotion.It is most commonly used in the service industry. For instance, it could be used to improve the efficiency of a housekeeping business.
  • The 4S’s Ishikawa diagram:
    The 4S diagram organizes information into four categories: suppliers, systems, surroundings, and skills.It is most commonly used in the service industry. For instance, a restaurant could use it to determine why the number of customers has declined over the past year.
  • Simple fishbone:
    A simple fishbone diagram has no predetermined causes or categories of causes.This is useful for organizations that want to create and set their own unique affinities. For instance, a software company will have very different affinities to a pet food manufacturer.
  • 3Ms/Man machine material fishbone:
    The 3M diagram, also known as the ‘man, machine, material’ fishbone, organizes information into three categories: manpower, machinery, and materials.It is most commonly used in the manufacturing industry. For instance, it could be used in a food processing plant to determine why product quality has declined.

Common uses of the Ishikawa Diagram

The Ishikawa diagram finds wide applications across various industries and sectors. Here are some common uses:

  • Quality Management: Ishikawa diagrams are extensively used in quality management processes such as Six Sigma and Lean Manufacturing.They help identify the root causes of defects, errors, or inefficiencies in processes, allowing organizations to develop targeted improvement strategies.
  • Problem Solving: When faced with complex problems, the Ishikawa diagram assists in breaking them down into manageable components.By identifying the underlying causes, teams can focus their efforts on addressing the core issues and implementing appropriate solutions
  • Process Improvement: Organizations striving for continuous improvement employ Ishikawa diagrams to analyze and optimize their processes.By visualizing potential causes and their relationships, teams can identify bottlenecks, inefficiencies, or variations that hinder process performance.
  • Product Development: Ishikawa diagrams are valuable during product development stages, particularly in identifying and resolving issues related to product quality, design, or functionality.They help teams ensure that all aspects of the product are thoroughly examined and optimized.
  • Risk Assessment: When assessing risks or potential failures, the Ishikawa diagram aids in identifying the underlying causes that may contribute to these risks.This enables organizations to develop proactive mitigation strategies and prevent potential problems.

How to create an Ishikawa Diagram

Creating an Ishikawa diagram involves a systematic approach to ensure comprehensive analysis.
Follow these steps to develop an effective fishbone diagram:

  • Define the Problem or Effect: Clearly articulate the problem or effect that you want to analyze.
    This serves as the starting point of the diagram.
  • Identify Major Categories: Determine the primary categories that are relevant to the problem at hand.These categories are typically the 6Ms (Manpower, Method, Machine, Material, Measurement, and Mother Nature), but they can be customized based on the specific context.
  • Draw the Fishbone Structure: Draw a horizontal arrow towards the right and label it with the problem or effect.Extend diagonal lines from the main arrow, representing the major categories identified in the previous step.
  • Identify Potential Causes: Brainstorm and identify potential causes within each category.These causes should be specific and actionable, allowing for targeted analysis and problem-solving.
  • Add Sub-Causes: For each potential cause, brainstorm sub-causes that may contribute to it.This step helps to further analyze and explore the depth of the problem.
  • Analyze and Prioritize Causes: Evaluate the potential causes and sub-causes to determine their significance and impact on the problem.Prioritize the most critical causes that require immediate attention.
  • Validate and Verify Causes: Engage stakeholders, subject matter experts, or cross-functional teams to validate the identified causes and gather additional insights.This collaborative effort ensures a comprehensive analysis and increases the accuracy of the diagram.
  • Take Action: Once the causes have been identified and validated, develop action plans to address them.Implement appropriate solutions, monitor their effectiveness, and iterate as necessary.


The Ishikawa diagram provides a structured approach to problem-solving and cause-and-effect analysis.

By visually mapping out potential causes, organizations can effectively identify the root causes of problems or effects, enabling them to implement targeted solutions.

Whether in quality management, process improvement, or product development, the Ishikawa diagram is a versatile tool that promotes collaboration, creativity, and continuous improvement.

By incorporating this powerful technique into problem-solving efforts, organizations can drive efficiency, enhance product and service quality, and ultimately achieve their strategic objectives.

Key takeaways

  • The Ishikawa diagram, or fishbone diagram, is a valuable tool for problem-solving and cause-and-effect analysis.
  • It helps identify and organize potential causes contributing to a problem or effect.
  • Common uses of the Ishikawa diagram include quality management, process improvement, problem-solving, and risk assessment.
  • Creating an effective Ishikawa diagram involves defining the problem, identifying major categories, brainstorming potential causes, and prioritizing them.
  • Collaboration and validation with stakeholders enhance the accuracy and effectiveness of the diagram.
  • Taking action based on the identified causes leads to targeted solutions and continuous improvement.
View Article Sources
  1. “Fishbone Diagram” – Cairo University
  2. “Fishbone Diagram: A Tool to Organize a Problem’s Cause and Effect” – University of Utah Health
  3. “Fishbone Diagram” – TechTarget