Malossa gas-condensate field is the deepest hydrocarbon deposit in production in Europe and one of only three in the world being regularly exploited with a reservoir pressure of over 15000 psi. The gas is overpressured to a large extent in the reservoir, its original pressure being 15 176 psi at a depth of 19 127 ft (water-gas contact). Drilling operations required a considerable effort, especially in casing design, mud and cement technology and drilling control. The very high pressure involved, and the presence in the production stream of corrosive components, originated serious problems in the first wells completed. Extensive use of metal-to-metal seals, use of special steels for the wellhead equipment, recourse to tubing with integral joints and use of an oil-base completion fluid permitted the solution of such problems. The periodical squeezing into the formation of a corrosion inhibitor proved to be beneficial in reducing the corrosion rate to a viable limit. Special care was given to the design and operating procedures of the well-killing system and of the surface equipment control and automatic emergency shutdown system. Malossa field is now in regular production and all problems seem to have been overcome.