This chapter aims to reconstruct Uztáriz’s personal and intellectual history. It highlights, among other aspects, his relationship with the influential group from Navarre who had settled in Madrid, his long sojourn in Belgium and the Netherlands, his informative travels around Europe, his posting to the Viceroyalty of Sicily as Treasury advisor, and his return to Spain at the height of the War of the Spanish Succession to serve the Crown in diplomatic affairs and on different councils. These stages are related with the vicissitudes of the 1724 first edition of the Theórica and the 1742 and 1757 re-editions, as well as the range of measures to tackle the country’s economic crisis set out in the work. The importance of examining the reports that Uztáriz wrote at the authorities’ request and other unpublished writings is also stressed.