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Security culture is the habits and shared awareness that shape how your team handles security day to day. Here's how to build it at a startup.
Security culture is the ambient awareness and shared habits that shape how a company handles security day to day. It's not always formalized. It shows up in small behaviors: locking your screen when you step away from your laptop, enabling 2FA on a new work account without being asked, flagging a suspicious email to the team instead of just deleting it. These aren't policies. They're the low-level instincts a team builds over time about what secure and insecure look like.
The reason these habits matter early is that they compound. A small team that treats security as shared background knowledge doesn't lose that instinct as it grows. A team that never built those habits doesn't develop them under pressure. Culture scales what's already there.
At most startups, security starts as one person's domain, often the CTO or a senior engineer who inherited it. The knowledge stays concentrated, the decisions stay quiet, and the rest of the company develops no intuition about what security means in their day-to-day work. Building a security culture means distributing enough context that other people can contribute, even in small ways, even when the CTO isn't in the room.
There's a version of security management that looks like this: the CTO finds a misconfiguration, fixes it quietly, and moves on. No mention in Slack, no note in the sprint, no conversation with the broader team. The reasoning is usually some version of "we don't want to alarm people" or "this is a technical matter."
But when security issues stay quiet, a few things happen. Engineers who notice something suspicious don't know whether it's worth raising, so they don't. Non-technical staff have no idea what the threat landscape looks like for the company, so they can't contribute to protecting it. The CTO becomes the single point of failure for everything security-related. And because no one is talking about it, no one is learning from it either.
One founder described their CTO's operating principle this way: "let's keep this down low, we don't want people to know how insecure we are." It felt protective, but what it actually created was a team that never developed any security intuition, and a CTO drowning in problems nobody else could see coming.
The alternative isn't over-sharing every CVE in the all-hands. It's treating security findings the way you'd treat a production incident: communicate clearly, resolve publicly, and learn from it.
When people know what kinds of problems get found, they start noticing more of them. A developer who hears "we found hardcoded credentials in a service last week" is going to think twice about what they're committing this week. A support rep who knows the company has been targeted by phishing attempts is going to look at suspicious inbound emails differently.
This is the virtuous cycle that keeping security siloed prevents: openness creates awareness, awareness leads to earlier reporting, earlier reporting leads to faster fixes, and faster fixes mean less exposure over time. It's not complicated, but it requires someone in leadership to decide that security is a topic the whole company is allowed to know about.
There's a difference between "everyone needs to know this" and "this is being handled." Getting that distinction right is what makes transparent security communication feel like a routine update rather than a crisis alert.
A few principles that help:
Security culture weakens fast when it only lives in engineering. Some of the most commonly exploited attack vectors run directly through non-technical staff, and the people who own those functions need enough context to recognize what a problem looks like in their world.
The right frame for this conversation is business, not technical. Security failures have real business consequences: deals that stall because you can't answer a security questionnaire, customers who want a SOC 2 you don't have, regulatory exposure in healthcare or fintech. These aren't abstract risks. They show up in pipeline reviews and board meetings. Non-technical leaders who understand that will stay invested in security without needing to understand the underlying mechanics.
On a day-to-day level, each function has a small set of things they need to know:
None of this requires extensive training. It requires clear, short communication about what to watch for and what to do.
The best time to build security awareness is before someone's first pull request or first customer call. Putting it in onboarding makes it part of how the company operates from the start, not a corrective measure introduced after something goes wrong.
What actually needs to be covered on day one is short:
That last item matters because people won't remember a verbal briefing two months later. A single internal document, even a short one, gives them somewhere to go when a question comes up.
What doesn't need to be covered in onboarding is a comprehensive security course. A 40-slide deck covering every possible threat vector produces people who click through and forget everything, not people who are any more aware than they were before.
A standing security review meeting, even a brief one, does something that ad hoc communication can't: it makes security a normal topic with a normal home in the calendar.
When findings get reviewed regularly, they stop feeling like crises and start feeling like operations. People know when the next discussion is, issues are being tracked, and the CTO isn't the only one carrying the context anymore.
What that meeting covers matters less than the fact that it exists and runs consistently. A short standing agenda might include: a summary of new findings from the past period, status on any open issues, anything notable from the threat environment, and any access or tooling changes that need review. Cross-functional attendance, even just a representative from ops or leadership, starts to build a shared vocabulary around security that compounds over time.
If you're building a security review process from scratch, our security review meeting guide covers how to structure it for a lean team.
It looks like a set of habits and norms that have become unremarkable. Security has a vocabulary the whole company shares, even if engineering is the only team that understands the technical details.
People report suspicious emails without being asked. A developer who spots something odd in a dependency flags it instead of shrugging. New hires know by the end of their first week who to tell if something seems wrong. The CTO still owns security strategy, but isn't the only person thinking about it.
Getting there comes down to a few consistent choices: talk openly about what you find, give non-technical teams the basic context they need to stay aware, make security part of how people start at the company, and revisit it often enough that it stops feeling exceptional. The habits you build early are the ones that scale.
The tooling that supports this should make findings visible and actionable without creating noise, so the security conversations you're having are about things that actually matter. Fencer is full stack security for startups who need signal, not volume.
Security culture is the set of shared behaviors, norms, and awareness that shapes how a company handles security day to day. At a startup, it's less about formal programs and more about whether people know what to do when they find a problem, and whether they feel safe raising it. A startup with a strong security culture doesn't necessarily have a security team; it has a team that treats security as a shared operational concern rather than one person's problem.
No. Security culture is mostly about communication and shared norms, not headcount. A CTO who talks openly about findings, runs a regular security review meeting, and gives non-technical staff basic awareness will build a stronger culture than one who treats security as a black box. The habits and norms that define security culture can be established by one person with a consistent approach, and they tend to self-reinforce once they take hold.
Connect it to things they already care about: customer trust, deal closings, their own accounts and tools. Sales teams respond to the framing of deals lost to failed security questionnaires. Support teams respond to examples of what social engineering attempts actually look like. Finance and ops teams respond to the risk of credential exposure through the tools they use every day. The goal is to give each function the minimum context they need to contribute, not to turn everyone into security thinkers.
At a minimum: using strong passwords and MFA, not sharing credentials, going through an approval process before adding new SaaS tools, and flagging suspicious emails or requests to the right person. These aren't demanding requirements, but they close some of the most commonly exploited gaps. Social engineering attacks and phishing frequently target non-technical staff because those are the paths of least resistance in companies where security awareness is uneven.
Lead with resolution, not exposure. "We found and fixed a misconfiguration in our S3 bucket settings" lands differently than "we had a security incident." Share what happened, what was done, and whether any follow-up action is needed from others. Regular updates, even brief ones, establish security as an ongoing operational topic rather than something that only comes up when there's a crisis.
Keep it short and practical: who owns security at the company, how to report something suspicious, basic hygiene expectations (passwords, MFA, software updates), and where to find the internal security runbook. The goal is awareness and a clear path to report, not a comprehensive training course. A short written reference they can return to later is more valuable than a detailed verbal briefing they'll forget within a week.
