Empowering Sustainable Futures

Dear colleagues, clients and shareholders,

Throughout 2023, the global risk landscape continued to evolve rapidly. The year saw breakthroughs in artificial intelligence, along with rising geopolitical tensions, growing cyber threats from malicious actors and numerous extreme weather events.

At the same time, the approach to environmental, social and governance (ESG) topics became increasingly complex against this backdrop. As stakeholders have deepened their understanding of ESG issues, expectations for public companies have shifted. Companies are expected to proactively navigate ESG risks by taking concrete steps to build resilience at all organizational levels. We have moved beyond commitments to taking action.

Our board collaborates with management on shaping ESG strategy, providing insights and perspectives on emerging risks and evolving stakeholder views on an ongoing basis throughout the year. In 2023, we endorsed management’s submission to the Science Based Targets initiative and management’s decision to conduct an ESG double materiality assessment to identify priority ESG topics in our rapidly changing environment.

This year’s report builds on previous disclosures to show how Marsh McLennan is taking action, whether by adding capabilities for clients, making progress toward commitments, expanding disclosures or, in some cases, staying the course. There is much to be proud of in Marsh McLennan’s performance, and we are delighted to present that progress in this year’s ESG report.

Sincerely,

Lloyd Yates

Chair, Board ESG Committee, Marsh McLennan

Dear colleagues, clients and shareholders,

Every day at Marsh McLennan, our more than 85,000 colleagues around the world help clients and communities see possibility and seize opportunity. With our specialized capabilities and expertise, we’re uniquely positioned to deliver actionable solutions that address their challenges—including

those that sit within the broad parameters of environmental, social and governance (ESG).

We help our clients clarify the complex so they can make critical decisions with confidence on issues related to everything from building climate resilience to expanding workplace diversity. The scope of this work – and the successful outcomes we help enable for our clients – often extends to communities and societies around the world.

And we hold ourselves to a high standard by modeling the behaviors we want to see in the world.

In 2023, for example, we submitted climate goals to the Science Based Targets initiative for validation as part of our commitment to achieve net-zero emissions across our global business operations by 2050. We have a strong enterprise risk management strategy in place, and our more than 85,000 colleagues around the world share one code of conduct. And knowing that different perspectives and backgrounds make our company stronger, more innovative and more reflective of the clients we serve, we continue to analyze and share more granular diversity representation data.

No company, industry or government can create change on its own. Addressing complex challenges such as climate change will require new partnerships, deeper trust and collaborative approaches.

It’s a privilege to contribute to collective action on global challenges, and the ESG progress outlined in this report is a testament to the extraordinary work our colleagues do every day to enable success for our clients and communities.

We look forward to the important work ahead, engaging with our colleagues, clients, shareholders, communities and governments around the world to meet challenges, build resilience and find opportunity.

All the best,

John Doyle

President and Chief Executive Officer