Gallagher Security announces key Australian appointments for regional and national roles.
Gallagher Security has announced a key national appointment, alongside 2 strategic roles within the NSW and ACT regions.
Tom Siler has been appointed national SMB and perimeter manager, following his success as enterprise business manager for the Victorian and Tasmanian sales team.
Scott Johnstone, director of sales – Australia, said Siler’s appointment reflects Gallagher’s strategy to strengthen national delivery while supporting experienced internal leaders to step into critical roles as the business scales.
“During his time with Gallagher, Tom has built a strong reputation for customer focus and market insight,” Johnstone said. “His understanding of SMB and perimeter, combined with his experience working closely with regional teams, positions him well to lead these nationally important portfolios.”

“His role will be centred on providing clear leadership and alignment across regions, working closely with teams to support sustainable growth and ensure we continue to deliver strong outcomes for customers and partners as this part of the business scales.
“Tom is a great fit for the role given his depth of experience and balanced approach to leadership, which positions him well to support both our end users and channel partners.”
Siler said he is proud to step into the role and continue building on Gallagher’s strong foundations.
“Gallagher has a commitment to developing leaders from within, and I’m excited to step into this national role,” he said. “My focus will be on supporting our teams and partners, strengthening consistency across regions, and ensuring we continue to deliver excellent results for end users,” says Siler.

Gallagher has also strengthened its NSW and ACT regions with 2 appointments.
David Issa, state manager – NSW and ACT, is pleased to welcome Tony Theissen and Alex Rajak to the Gallagher Security Australia team.
Theissen joins Gallagher as business development manager (NSW), bringing over 35 years’ experience across the security and technology industry.

“Theissen’s background spans technical delivery, leadership and enterprise sales, with a strong track record in driving strategic growth, particularly in delivering large-scale integrated solutions,” says Issa.
Rajak also joins as technical account manager (ACT), bringing 20 years of industry experience, including extensive work across high-security federal government and defence environments.
“Rajak’s background spans technical delivery, project management, solution design and bid management, with strong expertise in stakeholder engagement. His wealth of knowledge will be an asset to end users and channel partners across the region,” says Issa.
“Strengthening our national presence goes hand in hand with investing in leadership capability, ensuring we deliver consistent outcomes for our end users and channel partners while supporting continued growth across Australia. We are thrilled to welcome Tom, Tony, and Alex to Gallagher.”
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“Gallagher Security announces key Australian appointments for regional and national roles.”










