In this paper we spell out in detail the methodology underlying the construction of a new labour and capital stock dataset for Italy from 1861 through 2013. The existing seminal paper (Rossi, Sorgato and Toniolo 1993), much referred to in the literature, only covered the period 1911- 1990 for the former and 1890-1990 for the latter; moreover, it displayed little sectoral disaggregation. The labour dataset here presented includes both headcount (HC) and full-time equivalent (FTE) annual estimates of labour and is presented at a ten-sector level of disaggregation. Net capital stock annual estimates are instead broken down by asset type (means of transport; machinery and equipment; construction, in turn divided into residential and non-residential). Elaborations are conducted on the labour and capital series in order to gauge key features of the development and structural change of Italy's economy over more than 150 years of its unified history. The transparency and detail with which we here describe our methods and assumptions in our historical reconstruction open up the possibility of improvements and updates also by other scholars willing to take up the task. Meanwhile this dataset, combined with the new historical national accounts framework set up by a project coordinated by the Bank of Italy, finally makes a sectoral analysis of Italy's long-run development possible.