Gallagher names Aon’s Alistair Lester CEO of Private Equity and M&A, UK & EMEA

Insurance and reinsurance broking group Gallagher has appointed Alistair Lester as Chief Executive Officer (CEO) for Private Equity and M&A client practice, leading the firm’s existing transactional risks teams in the UK, Europe and the Middle East (EMEA).

In the role, Lester will oversee the expansion of the practice to deliver a comprehensive suite of services and solutions to businesses of all sizes engaged in acquisitions, mergers, and other transactions. He will report to Michael Rea, CEO of Gallagher’s broking business in the UK.

He will lead Gallagher’s UK & EMEA transactional solutions teams, which currently offer a range of solutions including tax, warranty & indemnity, litigation, structured credit, pre-M&A due diligence and post-deal/portfolio services.

Lester has nearly three decades of industry experience. Most recently, he served at global insurance and reinsurance broker Aon for the last eight years, as global co-CEO of M&A and transactional solutions.

In the past, Lester worked at broker WTW and brings extensive experience in M&A and post-deal value creation for both corporate clients as well as private equity and other alternative asset managers.

Rea commented on the appointmnet, “Alistair is one of the most experienced and respected private equity & M&A practitioners in the market, and he brings a track record of managing global teams and delivering revenue growth.

“Alistair will lead our existing talented transactional risks team across our UK Specialty division, as well as teams based in regional hubs across Europe and the Middle East. He will work closely with colleagues across the Americas, Australia and Asia as we develop the global Gallagher Private Equity and M&A practice.”

Lester added, “The role of risk and insurance professionals in private equity and M&A transactions has grown exponentially in recent years. Gallagher’s existing team is well established, and I am looking forward to working with them to build our presence in other key markets and further expand our solutions and services for clients.”

This morning, reported total revenue before reimbursement of $3.17 billion in Q2’25, compared to $2.73 billion in Q2’24, as the core brokerage and risk management segments combined to deliver 16% revenue growth, including organic revenue growth of 5.4%.