I'm forever grateful to Ian for two particular periods of influence and inspiration: the first in the early 1970s, and the second in the late 1990s, when Ian had allegedly 'retired'! As a young Treasury officer in the early 1970s, Ian's work in 'Economic Growth: Is it worth having?' was an exciting influence on the power of good economic analysis and a profound understaniding of national income accounting, lucidly expressed. More recently, Ian was most generous with his time and wisdom in commenting on work I was doing for the centenerary edition of the Treasury Roundup on measuring human progress. And in between and since, I continued to learn from Ian's erudition and tireless commitment to good statistics, good analysis, and good policy. He will be greatly missed