This document aims to provide a comprehensive review of irrigated agriculture in Italy with a particular emphasis on the water use efficiency (WUE) and water productivity (WP). The data presented include the country climatic characterization, water availability and withdrawal, sources of irrigation water, irrigable and irrigated lands, irrigation methods, irrigated crops and their growing parameters, experimental data on both biomass and yield WUE. The agronomic data of main crops, grown principally in Southern Italy environment, are taken into consideration. An analysis of: crop production functions, application of irrigation methods, and crop water requirements, in Italian agriculture is given. The presented crop coefficient data vary for a crop in respect to local climatic conditions, latitude, altitude, time of sowing and applied agronomic practices. Moreover, these data differ notable from those presented in scientific literature: it indicates a necessity for a local calibration and eventual revision of well-known existing FAO documents on crop water requirements and crop response to water. Finally, some common agronomic practices for enhancing WUE & WP have been described, focusing mainly on the situation of Southern Italy. This analysis, based on the evaluation of the national scientific literature and technical reports, has shown how these strategies should aim at increase of beneficial water consumption (transpiration) against the non-beneficial losses by: (i) increasing of marketable yield per unit of water transpired; (ii) maximizing transpiration consumption relative to evaporation losses; (iii) enhancing effective use of rainfall and water stored in the soil.