He began collaborating with the journalist Christopher Booker in the early 1990s, co-publishing on a range of issues, including the European Union. Their works advance a popular though academically disputed historiography of the UK's membership of the European Union. Their first book, "The Mad Officials: How The Bureaucrats Are Strangling Britain" (1994), focused on EU regulation in the UK, and was followed by "The Castle of Lies: Why Britain Must get Out of Europe" (1996) and "The Great Deception: Can the European Union Survive?" (2005). In 2004, he published a Bruges Group paper on the European Union's Galileo satellite navigation system.