Lean Manufacturing Approach and its integration into ISO 9001 QMSs

Introduction

In an increasingly competitive and globalized industrial environment, the Lean Manufacturing Approach represents a fundamental strategy within the reach of organizations to achieve a competitive position in the market. In order to meet these demands, many organizations have adopted Quality Management Systems (QMS) based on the ISO 9001 standard, as a fundamental tool to guarantee continuous improvement and the conformity of their processes with customer and market requirements.

However, the implementation of a QMS, although powerful, does not always ensure by itself the elimination of operational inefficiencies or the optimization of resources. This is where the Lean Manufacturing approach becomes strategically relevant. While ISO 9001 establishes a regulatory framework for managing quality, Lean provides the practical tools to improve operational performance, minimize errors and maximize value.

Integrating both approaches allows transforming the QMS into a living and dynamic system, focused not only on meeting requirements, but also on achieving sustainable operational excellence, which is the main objective of this article.

What is the Lean Manufacturing approach?

Lean Manufacturing is a management approach that originated in the Toyota production system, which has been adopted worldwide as an effective model for optimizing processes, reducing waste and improving organizational efficiency. The term was popularized in the 1990s by Womack and Jones (2023), who defined it as “a production system that uses less of everything (less human effort, less space, less tooling, less product development time, and less inventory) to deliver products of the highest quality and exactly what the customer wants.”

More than a set of tools, Lean Manufacturing is a value-oriented management approach that seeks to align all organizational processes to satisfy the customer with quality, speed and efficiency.

Although commonly associated with the manufacturing environment, Lean should be understood as a transversal approach, applicable to any type of organization, whether industrial, service, administrative or technological. Its potential lies in not prescribing closed rules, but in proposing flexible and universal principles that adapt to the specific reality of each company, as well as a group of tools applicable to organizations in different sectors, known as lean tools.

Considering Lean as an integral management approach implies recognizing that it is not a one-off tool or a passing fad, but a structured approach with logic, steps, phases, objectives and expected results. As an approach, Lean guides the organization in the transformation of its culture, processes and ways of working, generating sustainable improvements in key indicators such as productivity, quality, delivery times and customer satisfaction (Liker, 2021).

In today’s organizations, marked by volatility, pressure to reduce costs and the need to respond quickly to market demands, Lean Manufacturing has become a strategic tool for competitiveness. Its implementation makes it possible to identify systemic inefficiencies, encourage the active participation of teams and promote a practical approach to continuous improvement that perfectly complements the regulatory requirements of standards such as ISO 9001.

In short, Lean Manufacturing helps to “do more with less”, and guides organizations towards a way of thinking and acting focused on value, efficiency and sustained quality over time.

The strategic role of Lean Manufacturing in the implementation of a Quality Management System

Implementing a Quality Management System (QMS) under the guidelines of the ISO 9001 standard implies compliance with a series of documentary requirements or certification audits, as well as building an organizational structure capable of guaranteeing the product or service quality, continuously improving processes and systematically satisfying the customer. In this scenario, the Lean Manufacturing Approach provides a strategic dimension that significantly enhances the effectiveness of the system.

While ISO 9001 provides a normative framework that establishes what must be achieved – for example, managing risks, controlling processes, measuring customer satisfaction or continuous improvement – Lean Manufacturing offers methodologies, tools, principles and a practical philosophy on how to achieve these objectives in an efficient, agile and sustainable manner.

According to Melton (2005), integrating this tool in the implementation of a QMS allows, among other benefits:

• Ground continuous improvement beyond discourse: Lean turns improvement into a systematic, observable and quantifiable practice.
• Reduce inefficiencies from the beginning: Identifying waste (downtime and processes, excess inventory, among others) allows building a cleaner and more functional system from the design phase of the QMS.
• Actively involve operational teams: Through the Lean culture, quality ceases to be the exclusive responsibility of the management area and becomes a shared mission.
• Strengthen the process-based approach: It helps to visualize, measure and optimize workflows, facilitating the effective application of the standard’s principles.
• Generate added value for the customer: Both ISO 9001 and Lean coincide in their customer orientation, but Lean offers concrete tools to eliminate everything that does not contribute to that value.

In addition, by incorporating Lean from the design or adjustment stage of the management system, the risks of bureaucratization, excessive documentation burden or symbolic implementation are minimized. A Lean-influenced QMS is more agile, flexible, understandable for all levels and oriented to real results.

Therefore, more than a complementary tool, the Lean Manufacturing Approach should be seen as a strategic ally in the implementation and evolution of a Quality Management System. Its integration not only improves operational efficiency, but also reinforces the true meaning of the standard: to deliver sustained value to the customer through effective, controlled and constantly improving processes.

Principles of Lean Manufacturing applied to Quality Management Systems

The integration of Lean Manufacturing into a Quality Management System (QMS) based on ISO 9001:2015 is not only possible, but strategic. Both approaches share common objectives: continuous improvement, customer focus and process efficiency. However, Lean brings a set of fundamental principles that, when applied within the QMS, strengthen its operability and alignment with the quality culture (Bicheno, J., & Holweg, M. 2021).

The main Lean principles and their concrete application in the context of a QMS are presented below:

Getting it right the first time (Quality at source)

This principle states that quality should be built into the process, not inspected at the end. Instead of detecting errors, the focus is on preventing them at the source.
Application in the QMS:
Reinforces the standard’s requirements related to production control and service provision (clause 8). Helps design robust processes that minimize rework and ensure product conformity the first time, with a clear focus on processes (clause 4.4).

Eliminate waste

Lean identifies seven types of waste (muda): overproduction, lead times, transportation, excess inventory, unnecessary movements, overprocessing and defects.
Application in the QMS:
Contributes to compliance with the process-based approach (clause 4.4) by identifying activities that do not add value and can be eliminated or improved. This optimizes resources, reduces time and simplifies procedures within the system.

Continuous improvement (Kaizen)

Kaizen is the cultural basis of Lean thinking: a constant search for improvement, through small changes made by all members of the organization (Imai, 2012).
Application in the QMS:
It directly leverages clause 10.3 of ISO 9001 on continual improvement. Kaizen promotes that the system evolves organically, based on real data, staff participation and systematic feedback.

Pull Production

This principle implies producing only what the customer needs, when he needs it, avoiding overproduction and excess inventory.
Application in the QMS:
Strengthens customer orientation (clause 5.1.2 and 9.1.2) by ensuring that processes are synchronized with actual demand, avoiding producing more than necessary or with specifications that do not add value.

Flexibility

Lean promotes organizational structures and processes that can adapt quickly to changes, without losing efficiency or quality.
Application in the QMS:
Supports risk management (clause 6.1) and responsiveness to changing customer or stakeholder needs. A flexible quality system is more resilient, and can adjust with agility to new conditions.

Relationship with suppliers

Lean seeks to establish relationships of trust and collaboration with suppliers, rather than transactional links. It promotes joint improvement and transparency throughout the value chain.
Application in the QMS:
Contributes to the control of outsourced processes and the continuous evaluation of supplier performance (clause 8.4), transforming purchasing management into a strategic alliance oriented towards shared quality.

Focus on solutions

Beyond detecting problems, Lean teaches how to solve them at the root. This is achieved through root cause analysis, standardization of effective solutions and team participation in generating improvements.
Application in the QMS:
Strengthens corrective actions (clause 10.2) by allowing nonconformities to be addressed from a preventive, systemic and participative logic, avoiding the recurrence of failures.

In the following video we can see a classification scheme of common principles and tools in the Lean Manufacturing Approach.

The adoption of these principles within a QMS does not require reinventing the standard, but rather rethinking its implementation from a more efficient, dynamic and value-focused perspective, providing the cultural and operational foundations for the quality management system to not only meet the requirements, but to evolve with solidity and strategic sense.

How to implement the Lean Manufacturing methodology within an ISO 9001 QMS

Integrating the Lean Manufacturing methodology into a Quality Management System (QMS) should not be seen as an isolated, parallel or accessory project, but as a strategy that strengthens and energizes the implementation of the system itself under the guidelines of ISO 9001.

This integration requires a structured approach that combines the process management logic of the QMS with the operating principles of Lean, aimed at eliminating waste and generating value. The key steps to achieve this implementation effectively are described below:

Diagnosis of management system and processes

Before applying any Lean tool, it is necessary to understand the current state of the system and the critical processes. This involves:

• Identify key processes, support processes, strategic processes and their interaction (in line with clause 4.4 of ISO 9001).
• Perform value stream mapping (VSM) to visualize the current status and detect activities that do not add value.
• Establish initial performance indicators, cycle times, rework or rework levels.

Definition of strategic objectives aligned with Lean

The objectives of the management system should go beyond regulatory compliance. It is recommended:

• Establish quality objectives (clause 6.2) with a Lean approach: waste reduction, productivity improvement, defect elimination, delivery times.
• Link these objectives to the expected results of the system and to the customer’s needs.

Personnel training in Lean and improvement culture

Implementation requires the active participation of all levels. It is key:

• Train in basic Lean tools: 5S, Kaizen, PDCA, root cause analysis, standardization, etc.
• Promote a culture of continuous improvement, encouraging staff to propose improvements and identify problems in a structured way.
• Align training with the competencies required under clause 7.2 of ISO 9001.

Integration of Lean tools in the management system

Once the organization is ready, Lean tools are gradually integrated into the QMS:

• Apply 5S in work areas as part of the control of the operating environment (clause 7.1.4).
• Use Kaizen as a methodology to meet the continuous improvement requirement (clause 10.3).
• Establish visual standards and pull flows to optimize operational control (clause 8.5).
• Incorporate Lean methods in the management of nonconformities and corrective actions (clause 10.2).

Monitoring, measurement and improvement

The results-based approach requires that Lean improvements within the QMS be measured and analyzed. To this end:

• Establish key indicators related to efficiency, time, costs, defects, customer satisfaction.
• Implement PDCA improvement cycles to review the effectiveness of implemented Lean actions.
• Conduct internal audits (clause 9.2) to verify both system compliance and improvement through Lean practices.

A progressive and systemic path

The implementation of Lean within a QMS is not a one-time event, but a progressive process. Starting with pilot projects in critical areas and extending improvements gradually allows the system to mature without generating resistance. This integration, well managed, transforms the QMS into an agile, lively and value-oriented system, far beyond formal compliance with the standard.

Conclusions

The integration of Lean Manufacturing methodology into a Quality Management System based on ISO 9001 is not only possible, but highly recommended for those organizations seeking to move from regulatory compliance to operational excellence.

While ISO 9001 provides a solid framework for managing quality with customer focus, continuous improvement and process management, Lean Manufacturing delivers practical tools and principles to make that system work with efficiency, agility and real value orientation.

Incorporating Lean into the QMS allows to identify and eliminate waste, strengthen the culture of improvement, and turn work teams into active agents of change, all aligned with regulatory requirements. Lean principles are not only in line with the standard approaches, but also enhance them, generating a more dynamic system, less bureaucratic and oriented to sustainable results.

References

1. Liker, J. K. (2021). The Toyota Way: 14 Management Principles from the World’s Greatest Manufacturer (2nd ed.). McGraw-Hill Education.
2. Ohno, T. (2020). Toyota Production System: Beyond Large-Scale Production (Revised ed.). Productivity Press.
3. Womack, J. P., & Jones, D. T. (2023). Lean Thinking: Banish Waste and Create Wealth in Your Corporation (Updated ed.). Free Press.
4. International Organization for Standardization. (2015). ISO 9001:2015 – Quality management systems – Requirements. https://www.iso.org/standard/62085.html
5. Bicheno, J., & Holweg, M. (2021). The Lean Toolbox: The Essential Guide to Lean Transformation (5th ed.). PICSIE Books.
6. Imai, M. (2012). Gemba Kaizen: A Commonsense Approach to a Continuous Improvement Strategy (2nd ed.). McGraw-Hill Education.
7. Melton, T. (2005). The benefits of lean manufacturing: What lean thinking has to offer the process industries. Chemical Engineering Research and Design, 83(6), 662–673