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The Lessons Learned Handbook - Book Review

1 December 2015
Dr. Moria Levy
book cover

"The Lessons Learned Handbook: Practical Approaches to Learning from Experience" was authored in 2010 by Nick Milton, a well-known knowledge management consultant who began his career as the knowledge manager at BP (British Petroleum) in the early 2000s. This handbook explores the complete life cycle of lessons learned as conceived by Milton.

The book covers a range of topics, including:

Learning Systems for Lessons Learned

1. Lessons Learned Processes

2. Writing Lessons

3. Taking Action

4. Knowledge Dissemination

5. Learning from Lessons Learned

6. Governance

7. Safety Investigations

8. Tips

9. Summary

With nearly 200 pages of comprehensive and detailed content, this book covers this discipline and may be valuable for organizations and individuals involved in this field.

Learning Systems for Lessons Learned

The book begins by surveying 70 individuals to examine the status of lessons learned within various organizations. The findings reveal that 76% of organizations engage in lessons-learned activities, primarily focusing on major undertakings, such as projects. However, a significant majority of these organizations express dissatisfaction with the effectiveness of these efforts in improving performance. The primary reason for this dissatisfaction is the need for follow-up on lesson implementation, followed by issues related to insufficient management support and cultural challenges.

Milton highlights the historical significance of lessons learned systems, noting their recognition as early as the 15th century through a technique developed in Portugal by Henry the Navigator. Various definitions of lessons learned exist, all emphasizing knowledge, experience, and their potential impact on the work of others. Milton provides his definitions:

- Lesson: An experience-based recommendation (positive or negative) that is distilled, enabling others to enhance their performance in specific tasks or activities.

- Lesson Learned: A transformation in personal or organizational behavior resulting from assimilating knowledge derived from experience.

Multiple approaches to lessons-learned systems are available, and these approaches can be categorized in two ways:

1. Formality refers to whether the collection process is official or informal.

2. Nature of Connection- Indicating whether systems are used for data collection or fostering interpersonal connections.

Examples of these categories include:

- Formal Collection System: Maintaining a database containing organizational lessons learned.

- Informal Collection System: A system modeled after Wikipedia, integrating lessons learned.

- Official System for Connecting People: Expert networks and organizational knowledge communities.

- Informal System for Connecting People: Social networks and Internet communities are naturally managed best.

Milton advocates for an integrated approach, emphasizing the need for a comprehensive strategy.

Lessons Learned Processes


Several potential natural partners can participate in the process of identifying lessons learned. These partners include:

- Project Managers

- Team Leaders

- Project Knowledge Managers

- Organizational representatives involved in investigations

- Individuals focused on learning, such as Historians and chroniclers

- Team members

Collection Mechanisms:

The collection of lessons can be executed using well-established mechanisms commonly employed for gathering lessons, such as:

1. Post-Project Reviews: This mechanism originated at BP and involves retrieving lessons learned after a project or project phase. The process includes the following steps:

o Introduction: Aligning goals and demarcation

o Reviewing project objectives

o Examining project accomplishments

o Identifying issues worthy of deeper exploration, both successes and challenges observed

o Discussing issues and identifying learning points

o Closing any outstanding matters


o If there are more than 15-20 participants, it is advisable to divide them into subgroups.

o Consider recording the meetings to enhance credibility and accuracy.

2. AAR - After Action Reviews: A mechanism developed in the US military for gathering lessons learned at the end of an activity or task with a clear goal. It includes the following components:

o Clarification of expectations: What should have happened?

o Examination of the actual course of action: What happened?

o Analysis of the gaps

o Lessons to be drawn for the future

o Actions to be taken


Partners involved in the activity should be present.

3. Personal Learning Interviews: A mechanism familiar in the British Army for collecting lessons learned after each specific activity or mission (e.g., battle). The process involves:

o Preparing the interviewee: Explaining the process and coordinating expectations

o Conducting the actual interview, incorporating a structured set of questions (tree of three levels)

o Identifying supportive documents

o Conclusion


o It is recommended to accompany the interview with a recording.

o Without other options, interviews can be conducted by telephone, but this requires a higher engagement level.

4. Historical Learning: Learning in retrospect due to time constraints and the unavailability of personnel. The process includes:

o Aligning expectations, often involving a substantial scope of work

o Identifying interviewees

o Forming an interviewing team with suitable skills

o Conducting the interviews (with a structured set of questions as outlined below)

o Transcription

o Analysis of results

o Providing feedback to interviewees regarding the lessons learned

5. Evaluations of Parallel Processes: These may include a chapter on lessons learned and are recommended to be performed retrospectively.

6. Accident Investigation: Please refer to the separate chapter dedicated to this topic.

The Question Structure:

When implementing the above mechanisms, questions are asked and organized in a structure similar to a three-level tree:

1. Trunk: "What?" - Questions focus on the topic under investigation and analysis, encompassing key issues, success factors, obstacles, challenges, and branches derived from this level.

2. Branches: "How and why?" - Delving into the root causes to identify areas where learning can occur. Questions relate to the reasons for success, causes of deficiencies and mistakes, and explanations of phenomena. Leaves are derived from the answers to these questions.

3. Leaves: "Recommendations" - Looking towards the future, questions revolve around offering advice to others and determining actions if the same situation were to be repeated. Lessons are learned from the answers to these questions.

Writing Lessons

To enhance the learning process from a lesson, as defined above, the lessons must adhere to the following criteria:

1. Accessibility: They should be easily accessible and understandable to others.

2. Focus: Lessons should have a clearly defined and concentrated purpose to facilitate effective learning.

3. Practicality: Lessons should be practical and actionable.

4. Recommendation-Based: Lessons should be framed as recommendations rather than diagnoses.

It is advisable for lessons learned to be self-contained and structured as outlined below:

1. Header

2. Identification

3. Name and Date of Discovery

4. Status

5. Catalog: The subject and sub-topic relevant to the customer's domain.

6. Project

7. Context Description: The level of detail in this description should be tailored to the complexity of the lesson, its explanatory needs, its dependence on the scenario, and the intended audience.

8. Event Description: Provide a detailed account of the event from which the lesson was derived.

9. Root Causes Description

10. Lesson Description

11. Action Plan: A description of the actions to be taken, including responsible parties and their statuses.

12. Supporting Documents (if applicable): This may encompass drawings, flowcharts, videos, photos, stories, etc.


When crafting the lessons (as well as making updates below), it is crucial to consider the end-users perspective.


- Since composing lessons involves screening and processing, quality control should be integral to the process.

- Lessons learned should lead to concrete actions.

Taking Action

As previously emphasized, each lesson should yield actionable steps for practical application, with only a few exceptional cases, including:

1. Reinforcement of Prior Lessons or Existing Guidelines.

2. Instances with Extremely Low Probability of Recurrence.

3. Situations where only distinctions exist and no actual lessons are derived.

Various types of actions that may be encountered include:

- Repair Operations: Examples encompass equipment or machinery replacement and contract modifications.

- Further Investigation: This involves conducting laboratory experiments or a detailed examination of a specific topic during subsequent iterations.

- New Documentation or Updating Existing Documentation: This includes professional theories, work procedures, checklists, FAQs, and more.

- Recommendations: Recommendations should be user-centric, comprehensive, integrated with multimedia, and easily accessible.

- Updating Training or Learning Materials.

- Passing on the Lesson to Others for Decision-Making.


- Base actions on root causes rather than symptoms.

- When a decision falls beyond one's authority, escalate it to higher managerial levels.


1. Identify those responsible for implementing the actions, including technical authorities, content specialists, community leaders, and applicable R&D teams. Integrating these responsible parties into the learning cycle is recommended to ensure alignment with the task.

2. Monitor the progress of the activities and mark their completion at the conclusion.

Knowledge Dissemination

The dissemination of acquired knowledge holds paramount significance. Several channels for knowledge dissemination encompass:

- Blog

- Newsletter

- Community Discourse/Forum

- Email distribution

- Process Change RSS Feeds

- Dedicated Software

- Integration into training materials

- Integration into workflows (as elaborated in the subsequent section below)

Learning from Lessons Learned

Lessons learned can be accessed at various levels:

Integration into Work Processes:

- Peer Review: This involves engaging with colleagues at the project's outset to discuss another project of a similar nature and its associated lessons.

- BAR (Before Action Review): This complementary process to AAR (After Action Review) addresses five key questions:

1. What are the expected outcomes?

2. What challenges are anticipated along the way?

3. What lessons can we draw from similar situations?

4. What processes should be followed?

5. How can we enhance performance based on past experiences?

- Technical Limits: A mechanism employed at Shell that combines learning from lessons, knowledge exchange, and innovation. This process divides tasks into manageable segments, each undergoing analysis to determine its necessity, critical path relevance, and early realization strategies. Risk analysis and action plan updates are also integral components.

- Knowledge Management Planning: Conducted at the project's onset, this process analyzes the critical knowledge required for the project and identifies existing documents that can aid in implementing new activities.

- Scenario Planning: This process involves raising and analyzing various scenarios, leveraging insights from past lessons.

Access to Documented Lessons:

Lessons Learned: These lessons can be published and searched for (Pull & Push) within both work documents and the lessons. Lessons learned adhere to the detailed structure outlined in the lesson writing chapter and may be presented as a portal or wiki.

Access to Lessons Learned and Informal Knowledge That Hasn't Been Documented:

- Knowledge Communities and Social Networks

- Baton Passing, Knowledge Handover, Peer Assist: Utilizing interactions with other project teams to convene and learn from their knowledge.

- Encouraging Organizational Discourse: This includes fostering open work areas, seating areas, corporate yellow pages, roundtable meetings, and other avenues for open communication.


It is widely acknowledged that effective technologies for managing lessons learned are insufficient; governance is equally essential to ensure effective learning.

Recommendations for managers:

1. Communicate employee expectations:

o Emphasize the importance of focus.

o Specify the details of the required actions.

o Identify those responsible for executing these actions.

2. Provide employees with the necessary tools and guidance:

o Define roles and responsibilities.

o Outline processes to be followed.

o Offer the support of computing required.

3. Monitor employees' adherence to requirements:

o Implement monitoring and control mechanisms, including:

o Utilization indices.

o Compliance with the established lesson standards.

o Assessing results and the presence of improvement.

o Establish a system for rewarding compliance and appropriately addressing deviations from expected actions.

Safety Investigations

Johnny Martin, an expert with extensive experience in the field, has authored the chapter on Safety Investigations. The investigation process comprises the following stages:

1. Preparation: This stage involves logistical preparations for commencing the mission, including details down to the first aid level and essential items to be taken.

2. Accident Reporting and Initial Actions: It is advisable to utilize checklists to gather initial data regarding:

o Injured individuals and the nature of their injuries.

o Incident details.

o Potential witnesses or individuals to be questioned.

3. Formal Analysis: This phase includes:

o Interrogating individuals.

o Conducting interviews.

o Examining equipment.

o Inspecting premises.

o Thoroughly investigating data.

o Organizing evidence.

o Summarizing the analysis.

o Identifying corrective actions and lessons learned.

o Preparing a comprehensive summary report.


Here are some refined tips for implementing a lessons-learned program within the organization (the book contains 100 tips):

1. Promote Openness: Encourage transparency and avoid concealing errors.

2. Embrace a Non-Hierarchical Culture: Create an environment without rigid hierarchies.

3. Avoid Judgment: Foster a non-judgmental atmosphere.

4. Prioritize Learning Over Blame or Praise: Focus on learning rather than assigning blame or praising.

5. Show Respect and Listen to All: Respect everyone's input and actively listen.

6. Collaborate with Participants: Work closely with individuals directly involved in the activity rather than outsiders.

7. Address Significant Issues: Concentrate on substantial rather than minor details.

8. Encourage Constructive Discussions: Promote constructive discussions instead of arguments.

9. Utilize Appropriate Techniques: Use techniques suitable for the nature and complexity of the activity.

10. Follow an Organized Methodology and Templates: Implement an organized methodology and accompanying templates.

11. Prepare Interviewees: Ensure interviewees are well-prepared for their participation.

12. Prioritize Thorough Analysis: Avoid rushing to solutions and allow time for in-depth analysis.

13. Employ Clear and Simple Writing: Write with the target audience in mind, emphasizing clarity.

14. Present Lessons Separately: Keep lessons learned distinct and avoid presenting them as a single, integrated document.

15. Share Knowledge on Updating Processes: Utilize existing blogs and communication channels to disseminate information about updating processes.

16. Reward Improvement and Quality Content: Recognize and reward individuals for contributing to improvement and offering valuable content, not just for contributing lessons.


The realm of lessons learned encompasses the expansive landscape of knowledge management. The book outlines the process and delves into additional knowledge management mechanisms (briefly summarized here in the abstract). It educates readers about the depth and significance of the lessons learned domain and emphasizes the richness and, even more importantly, the importance of integrating these lessons within the organization. The ultimate goal is to harness this acquired knowledge to enhance performance and improve the organization.

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