Let’s says your organization has experienced a cybersecurity incident that had no material impact on the business but nevertheless rattled the security team and got the attention of senior management. Somehow the attack slipped past the monitoring tools in place before it was detected and mitigated. It was a close call.
So now what? This is when a post-incident review, a key component of any cybersecurity program, needs to kick in. These initiatives, also referred to as after-action reviews, hotwashes, or debriefs, are structured processes organizations use to analyze past events, projects, or initiatives to identify what went well, what didn’t, and how performance can be improved in the future.
They are vital for making continuous improvements in incident response (IR), says David Taylor, a managing director at global consulting firm Protiviti.
“Our post-incident review playbook is essential for strengthening our cybersecurity defenses,” Taylor says. “We use this playbook after significant responses and continuously enhance it as needed to elevate our team capabilities. This structured approach fosters deep conversations and ensures that lessons learned are effectively integrated into future response plans, leading to more resilient and efficient incident management.”
“An effective post-incident review isn’t just about assessing outcomes, it’s about capturing context, identifying structural issues and sharing learnings beyond the immediate security team,” says Eireann Leverett, a security researcher and advisor to the Forum of Incident Response and Security Teams.
A strong post-incident review strategy has several key components and attributes. Here’s how to ensure your after-action debriefs lead to better performance in the future.
Conduct analysis while details are fresh — and establish a thorough timeline
When analyzing security events, timing is everything. Waiting months or even weeks to conduct the review increases the risk of forgetting important elements of the attack and its aftermath, preventing security leaders and teams from getting a true sense of what happened.
“Conducting the post-incident review soon after the incident ensures details are fresh in everyone’s minds, reducing memory lapses and maintaining a sense of urgency,” Taylor says.
Timeliness also enables reviewers to create an accurate timeline of events.
“One of the first things to do is piece together what actually happened — from the first sign of trouble all the way through to when things were brought under control,” says Heather Clauson Haughian, co-founder and co-managing partner at CM Law, a privacy and data security attorney.
“Rebuilding the timeline helps everyone understand where delays or mistakes may have occurred, but also where things went right,” Haughian says. “It’s basically the story of the incident — and getting that story straight is the foundation for learning from it. By understanding the chronology, organizations can identify specific moments where things went well [and] where they didn’t.”
Perform a root-cause analysis
Your post-incident review must include a root-cause analysis, Taylor says. “Identifying the underlying issues that caused the incident is essential for avoiding future cyber incidents,” he says.
The post-incident review team should examine the root causes of the incident, whether they are technical, procedural, or human-related, and implement corrective actions and preventive measures to improve the organization’s security, Taylor says.
“Identifying the root cause of the incident is critical,” says Michael Brown, field CISO at IT Services and IT Consulting provider Presidio. “Teams need to determine if this was a technical vulnerability, process/technology gaps, or human error. This analysis ensures teams address the underlying issues, not just the symptoms.”
With a root cause analysis, “you want to figure out why the incident happened in the first place,” Haughian says. “Was it a missed software update? A phishing email someone clicked on? Or maybe it was a process that didn’t work as it should have. This is where you dig into the root cause — not just what went wrong, but why it went wrong. If you don’t figure that out, you’re likely to run into the same issue again.”
Evaluate team performance and identify training gaps
Part of the review needs to be focused on evaluating the team’s performance in relation to established procedures, such as the cyber incident response plan, Taylor says. This is essential for improving overall capabilities, he says.
“This focus area can provide valuable information for innovative improvements, identifying training gaps, and updating outdated documentation, [and] thereby reducing inefficiencies during a response,” Taylor says. “This effort frequently contributes to refining response protocols and enhancing training programs.”
At Presidio, the post-incident review includes a structured evaluation of the incident response team’s performance across a variety of dimensions, Brown says. These include detection and containment, timeliness, communication clarity, cross-functional coordination, and adherence to procedures and escalation protocols.
“It’s essential to review how security teams and stakeholders responded and performed,” Brown says. “This helps determine and highlight strengths and weaknesses in incident response plans [and] is critical in improvements in the future and highlights gaps for training or staff changes.”
Include comprehensive analysis of business impacts
Understanding the impact of an incident is multifaceted and includes both quantitative and qualitative analyses, Brown says. On the quantitative side, enterprises need to consider impacts such as financial losses, market share decline, and client cancellations following incident disclosure, he says.
The qualitative impact analysis should include areas such as whether business continuity was significantly hindered, compliance violations were reported to regulatory authorities, or the business experienced reputational damage via negative media coverage or social media backlash, Brown says.
“Discover and analyze the scope of the incident’s impact, including operational, financial, legal, and reputational impact,” Brown says.
Capture context to ensure after-action review includes adequate depth
A key factor of a post-incident response analysis is looking at the context of the incident. Capturing context is vital for ensuring an incident timeline is comprehensive enough for teams to learn from.
“Document the incident as it evolved, not just as it ended,” Leverett says. “Too often, post-incident reviews skip over the context in which decisions were made. That’s a mistake. Incidents unfold over time. The team working on it rarely has all the facts up front.”
Each new discovery — the initial breach, the scope, the toolset used by attackers — shifts the team’s investigative goals, Leverett says. “What starts as containment can turn into eradication or recovery,” he says. “Tracking when and why those shifts happened helps everyone later understand what actions were taken and why.”
Recognize that effective debriefing requires cross-functional collaboration
While the CISO or other senior cybersecurity or IT executive needs to lead the post-incident review, it’s important to include a range of individuals who can contribute insights.
“Start with the team that worked the incident: IR, IT, and the CISO. But don’t stop there,” Leverett says. Organizations should broaden the review team to include people from governance, risk, and compliance (GRC), legal, and risk management. “They can connect incident root causes to broader policy gaps,” he says.
It’s also good to involve finance and human resources. “They can learn about breach costs, credential revocation needs, and employee impacts,” Leverett says. Depending on the incident, maybe even include board-level stakeholders.
“Their presence signals strategic prioritization and helps link technical findings to governance-level risk conversations,” Leverett says. “Later, you can selectively share learnings with external partners,” such as trusted third parties.
Key business owners affected by the incident should share their experiences, to identify changes in operations related to the response, Taylor says. And inviting C-suite executives to take part in the review can ensure strategic perspectives are considered.
It is important that everyone has an equal voice in meetings to discuss the review, regardless of their title or role, Taylor says. “This promotes a comprehensive understanding of the incident and fosters a collaborative environment,” he says. “Inclusive participation helps to uncover diverse viewpoints and solutions.”
Focus on structural learning over individual blame
Looking to point figures at individuals or groups during the review process might not be productive.
“Move the focus from blame to learning and improvement, which is essential for uncovering the true sequence of events, understanding decision-making processes, and identifying all contributing factors to both what went well and what went wrong,” Haughian says. This approach can help inform strategic decisions about tools, training, and policies going forward,” she says.
“The point isn’t to ask, ‘Did this person make the right call?’” Leverett says. “It’s to ask, ‘Were they equipped to make good decisions under the circumstances?’ Could better documentation, funding, or tooling have enabled faster or safer outcomes? That’s a more productive conversation.”
Above all, post-incident reviews should be learning exercises, not interrogations, Leverett says. “They should surface the constraints and tradeoffs the team faced and evaluate decisions in the context they were made,” he says. “Invite not only those who worked the incident, but those who can learn from it. That’s how you build a culture of resilience.”
Create a clear plan of action going forward
All the lessons learned in these steps will not be of much use if they are not turned into actions, Haughian says.
“This means writing down what needs to be fixed or improved, who’s going to take care of each task, and when it should be done,” Haughian says. “It might be things like updating software, changing policies, or running new training sessions.”
Whatever the takeaways are, the follow-up is what makes the post-incident review useful because without actionable recommendations, such a review is merely an academic exercise. Assigning ownership and deadlines ensures accountability and drives the implementation of improvements such as updating incident response plans and playbooks, improving training, or investing in new technologies or resources, Haughian says.