John Llewellyn is a prominent macroeconomic policy expert and speaker, recognized for his extensive knowledge in macroeconomics, climate change economics, and the economic growth of Asia. He is the principal at Llewellyn Consulting, where he specializes in macroeconomic analysis and the economics of climate change.

Llewellyn's career includes significant roles in both the public and private sectors. He served as the Global Chief Economist and Senior Economic Policy Advisor at Lehman Brothers, where he provided insights during critical economic periods. Prior to this, he spent nearly two decades at the Organisation for Economic Cooperation and Development (OECD) in Paris, where he held various positions, including Head of International Forecasting and Policy Analysis and Chef de Cabinet to the Secretary-General. His academic background includes nearly ten years at the University of Cambridge, where he was a Fellow of St. John's College and contributed to the Faculty of Economics.

Throughout his career, Llewellyn has published extensively on topics such as international economic policy, economic forecasting, and the implications of climate change. His expertise has made him a sought-after speaker at international conferences and events, where he addresses issues related to economic growth, sustainability, and the challenges posed by climate change.

Llewellyn's credibility is further established through his affiliations with various economic organizations and his contributions to policy discussions at high levels of government. His insights into the economic dynamics of Asia and the impact of climate change on global economies have positioned him as a leading voice in the field of macroeconomics.