This book offers the first intellectual biography of the Anglo Australian economist, Colin Clark. Despite taking the economics world by storm with a mercurial ability for statistical analysis, Clark's work has been largely overlooked in the 30 years since his death. His career was punctuated by a number of firsts. He was the first economist to derive the concept of GNP, the first to broach development economics and to foresee the re-emergence of India and China within the global economy. In 1945, he predicted the rise and persistence of inflation when taxation levels exceeded 25 per cent of GNP. And he was also the first economist to debunk post-war predictions of mass hunger by arguing that rapid population growth engendered economic development. Clark wandered through the fields of applied economics in much the same way as he rambled through the English countryside and the Australian bush. His imaginative wanderings qualify him as the eminent gypsy economist for the 20th century. Alex Millmow was formerly an associate professor in economics at Federation University Australia where he is now an honorary research fellow. He is also an honorary research fellow at the School of History, Australian National University. He is currently President of the History of Economic Thought Society of Australia. His last book was A History of Australasian Economic Thought IN 2017.