Most organizations run offense and defense as separate events. The red team breaks in, writes a report, and leaves. The blue team reads it weeks later, patches what it can, and never learns whether its detections would have caught the attack.
Purple teaming closes that gap. Attackers and defenders work the same exercise together, in real time, so every technique tested becomes a detection tuned, a gap logged, or a control proven.
What purple teaming is (and isn’t)
Purple teaming is a collaborative exercise where the red team emulates real adversary behavior and the blue team watches, detects, and responds alongside them. It is a way of working, not a third team you have to hire.
It is:
- Transparent. Defenders know what is being executed and when, so they can check their telemetry against ground truth.
- Iterative. A technique that slips past detection gets tuned and re-run until it fires.
- Threat-informed. Scenarios map to the adversaries that actually target your industry, usually tracked against MITRE ATT&CK.
It isn’t:
- A replacement for a blind red team engagement. You still need an unannounced test to measure real-world response.
- A tabletop. Purple teaming runs real techniques against real systems.
- A checkbox. The output is improved detection coverage, not a PDF.
How a purple team exercise works
The loop repeats for every technique in scope. Nothing moves forward on a promise to fix it later: a gap is tuned and retested while red and blue are still working together.
Purple teaming vs. red teaming and penetration testing
A traditional report tells you what the attacker did. A purple team exercise tells you what your defenses saw while they did it.
| Traditional red team / pentest | Purple team | |
|---|---|---|
| Blue team involvement | After the fact, via report | Live, during execution |
| Main output | Findings and remediation list | Validated and tuned detections |
| Detection gaps | Inferred | Measured technique by technique |
| Fix verification | Next year’s test | Re-run the same day |
| Knowledge transfer | Limited to the report | Analysts learn attacker tradecraft hands-on |
The biggest payoff is speed. Gaps that would sit open until the next annual test get closed while both teams are still in the room.
How to start a purple team program
You don’t need a mature SOC to start. You need logging, a willing blue team, and a scoped list of techniques.
- Pick a threat. Choose one adversary or campaign relevant to your sector and pull its techniques from ATT&CK.
- Check your telemetry first. Confirm endpoint, identity, and network logs actually reach your SIEM before anyone runs an attack.
- Keep the first scope small. Ten to fifteen techniques done well beats a hundred skimmed.
- Track every result. For each technique, log whether it was prevented, detected, alerted, or missed.
- Re-test before you close. A detection isn’t fixed until the technique runs again and fires.
Common purple teaming mistakes
- Treating it as a show. If the red team performs and the blue team watches, nobody learns. Defenders should drive the questions.
- Skipping the retest. Tuning a rule without re-running the technique is guessing.
- Ignoring prevention wins. A blocked technique still needs an alert. Silent blocks hide repeated attempts.
- One and done. Environments change. Run purple team cycles quarterly or after major changes.
Purple teaming FAQ
What is the difference between red, blue, and purple teams? The red team emulates attackers, the blue team defends, and purple teaming is the practice of running both together so findings turn directly into better detections.
Does purple teaming replace penetration testing? No. A pentest or blind red team engagement measures how you respond to an unknown attack. Purple teaming improves the detections that response depends on. Most mature programs run both.
How often should you run a purple team exercise? Quarterly is a common cadence, plus after major changes such as a new EDR, SIEM migration, or cloud move.
What do you need before your first exercise? Centralized logging, a blue team with time to participate, and a short list of techniques tied to threats that target your industry.
The bottom line
Offense finds the gaps. Defense closes them. Purple teaming makes sure both happen in the same week instead of the same year.
At Brackish Security, we run purple team engagements alongside our network, web app, and AI red teaming work, so your defenders walk away with tuned detections, not just a findings list. If you want to know what your SOC actually sees, get in touch.