3.1 This book, as its title suggests, is primarily concerned with the impact of English law upon claims involving debts, losses or damage that may call to be measured in a foreign currency. As will be shown, English law underwent a radical change in the 1970s, from which time the previous regime under which claims could be brought only in sterling was overthrown in favour of a system that allows judgments to be given in a foreign currency where that is more appropriate. The change became necessary, or highly desirable, because of the volatility of currency exchange rates and the fall of sterling from the dominant position it had enjoyed until earlier in the 20th century. Perhaps the change might have occurred sooner. At any rate, now that the new regime has been introduced it has led to a reappraisal of some fundamental aspects of claims for debts and in contract and in tort, and has occurred at a time of other developments in the law, particularly regarding determination of the date as at which damages are assessed.