As businesses scale past 100 people, expectations around information security start to change. Clients ask more questions. Procurement processes become more rigorous. Internal complexity increases. What once worked informally no longer holds up under scrutiny.

We sat down with Rob Miller, Senior Director at Public Digital and a LeftBrain client, to understand what it takes to successfully implement ISO 27001 in a growing organisation, and what other businesses can learn from the process.

1. Understand why ISO matters for your growth

For Public Digital, ISO 27001 was not driven by compliance alone. It was about building trust with clients and supporting the next stage of growth.

“As we grow, managing information well becomes increasingly important, giving clients confidence that their data is handled properly.”

As organisations scale, especially across sectors like government, enterprise and global institutions, demonstrating strong information governance becomes essential. ISO 27001 provides a recognised framework that signals maturity and reliability.

2. Treat ISO as more than a certification exercise

One of the most common mistakes is approaching ISO 27001 as a box-ticking exercise. For Public Digital, the value came from embedding better ways of working across the organisation.

The process helped raise the profile of information management internally and brought together teams from across the business: “It’s brought people from across the team into the work, which has really helped us embed some of the practices that we want to do.”

When approached properly, ISO becomes part of how the organisation operates, not something separate from it.

3. Bring in experience early

Having the right support made a significant difference to how quickly and smoothly Public Digital progressed through ISO 27001: “Having people who’ve been through the process before help you go through the journey was really important because it meant that we weren’t guessing.”

With the right guidance, the team were able to move quickly and confidently, supported by proven frameworks and practical toolkits.

For growing businesses, this kind of support reduces friction and helps avoid common pitfalls.

4. Expect a learning curve and step back when needed

ISO 27001 introduces a level of structure that can feel overwhelming at first, especially when working across multiple teams and systems: “We sort of plunged into the detail very quickly and we had to kind of extract ourselves to make sure that we had the picture.”

For Public Digital, taking a step back to understand how everything connected was a key turning point: “We were doing stuff but we didn’t really see the picture… then we sat down and dug into it and got a really good sense of how it all worked.”

Building that clarity early helps teams move faster later in the process.

Embed ISO into everyday operations

The real impact of ISO 27001 comes after certification. For Public Digital, the process helped establish stronger operational practices across the business: “Going through the process has really helped us raise the profile of our information management across the organisation.”

Registers, controls and documentation are now embedded into day-to-day work, making ongoing compliance much easier to maintain.

This is where ISO shifts from a project into a long-term operational advantage.

6. Use ISO to strengthen client confidence

For growing businesses, especially those working with enterprise or public sector clients, ISO 27001 plays a key role in building trust.

Beyond the certificate itself, the process demonstrates that the organisation has taken a structured, considered approach to managing information.

Building ISO into your growth strategy

For organisations scaling beyond 100 employees, ISO 27001 is not just about compliance. It is about creating a foundation for sustainable growth, stronger client relationships and clearer internal processes.

As Rob’s experience shows, the key is to approach ISO as a strategic initiative, not just a technical requirement. With the right mindset and support, it becomes a way to align security, operations and culture as the business grows.