Red Team vs Blue Team vs Purple Team: What’s the Difference?

Red, blue and purple teams describe three different approaches to testing and defending a business’s security. They are easy to mix up, partly because the names sound like a set and partly because the same people sometimes play more than one role.

The difference comes down to what each team is trying to do: the red team attacks, the blue team defends, and the purple team gets the two working together. Below, we explain how each one works and when your business would actually use it.

Red, blue and purple team cybersecurity jargon takes a moment to get used to. If there’s a term you’re unfamiliar with, our A-Z cybersecurity glossary is here to help.

Red team vs blue team vs purple team at a glance

If you only need the short version, this is how the three compare.

The rest of this article looks at each in turn.

What is a red team?

The red team are the attackers. They are usually external ethical hackers, hired to break into your systems the way a real adversary would, using methods such as phishing, exploiting technical flaws or even physical entry, all while working to stay undetected. The point is to find the weak spots before a criminal does. We cover this in full in our guide to what red teaming is.

What is a blue team?

The blue team are the defenders. They are usually your own IT and security staff, the people responsible for monitoring systems, spotting suspicious activity and responding when something goes wrong.

In a standard red team engagement, the blue team are not told a test is taking place. That can sound unfair, but it is deliberate. If they believe the attack is real, their response shows how your defences hold up under genuine pressure, rather than how they hold up when everyone is braced for trouble. Beyond the moment of an attack, a blue team’s work also covers the slower, ongoing tasks: hardening systems, tuning their monitoring, and closing the gaps that a red team exposes.

What is a purple team?

Purple teaming is what happens when the red and blue teams work together instead of against each other. The name, rather obviously, comes from mixing red and blue. In purple teaming, rather than the attackers trying to slip past the defenders unnoticed, the two sides share what they are doing as they go. The red team explains the techniques being used, and the blue team checks whether they can see and stop each one.

In practice, purple teaming is usually an activity rather than a standing team. Because red teamers are often third-party specialists, the two groups may still operate separately, but they compare notes throughout the engagement and build a feedback loop that sharpens both attack and defence. The result is a clear picture of which attacks you can detect, which you cannot, and what to fix first.

This approach suits businesses that want to improve their detection and response quickly, without waiting out a fully covert red team engagement. It is also one of the best ways to get more from your internal team, who learn directly from watching how a real attacker operates.

When does your business need each?

Most businesses do not pick just one of these. Instead, they use them at different points, depending on what they need to learn.

A red team engagement makes sense once you have defences worth testing and you want to know how they would hold up against a determined attacker. It is the closest thing to a real breach without the damage. If a full engagement feels like too much for a first step, a micro red team tests your highest-risk scenarios in a shorter, lower-cost format.

A blue team focus should come first when your day-to-day monitoring and response need strengthening. There is little point running a covert red team if no one is ready to detect and act on what it finds, so the defensive groundwork usually has to be in place before the rest is worthwhile.

Purple teaming is the right call when you want the two sides to learn from each other and improve detection fast. It turns the findings from a simulated attack into specific, practical changes, which is why it works well as a follow-up to a red or blue team exercise rather than a standalone job.

It’s worth highlighting that some environments narrow the decision further. In operational technology and industrial settings, testing has to work around systems that cannot be taken offline, which changes how these exercises are run. We cover that in our guide to red teaming for OT and ICS environments.

If you are not sure which fits your situation, our team can help you scope it. You can read about our red and purple teaming services or book a call.

Red team vs blue team vs purple team FAQs

Red team vs blue team: what’s the difference?

The red team are the attackers and the blue team are the defenders. The red team simulates a real attack to find weaknesses, while the blue team works to detect and respond to it. Running the two against each other shows how your security performs in practice, not just on paper.

Is purple teaming a team or an activity?

Usually an activity, because most businesses do not employ a permanent purple team. Instead, their existing red and blue teams collaborate for a particular engagement, sharing techniques and results so both sides improve.

What is red team vs blue team vs purple team testing?

It is a way of describing three approaches to the same goal. Red team testing probes your defences like an attacker, blue team testing measures how well you detect and respond, and purple team testing has the two work together to close the gaps faster.

Which is better, a red team or a blue team?

Neither is better because they do different jobs and depend on each other. A red team has little value if there is no blue team able to act on its findings, and a blue team improves most when it is tested by a capable red team.

Can the same people be on the red and blue team?

In a covert red team engagement, no, because the test relies on the defenders not knowing. In a purple team exercise they can, since the whole point is collaboration. Many providers keep dedicated offensive specialists for the red team role regardless.

Conclusion

Red, blue and purple describe three ways of working towards the same outcome: keeping your business secure. Red teams show you how an attacker would get in, blue teams keep watch and respond, and purple teams bring the two together so each improves the other.

Most security programmes use all three over time, in the order that suits where they are. If you want help working out where to start, book a call and we can talk it through.