This presentation refers to the convenience of drilling a slanted well in a multilayer reservoir where the lateral continuity was difficult to determine. The Loma Negra Oil Field was discovered by Petrolera Argentina San Jorge in 1996. The field is located in the western part of Argentina and the oil production is coming from 3 different reservoirs, Punta Rosada Fm, Lajas Fm and Pre-Cuyo Fm at depths of 8200 ft, 9200 ft and 10200 ft respectively. With the objective of developing the Pre-Cuyo reserves (represent 48% of the total P1 undeveloped reserves) an extensive study have been performed to analyze different alternatives to be applied in multilayer reservoirs as the case of Pre-Cuyo fm. The Pre-Cuyano sediments are alluvial fan deposits. The reservoir is formed by conglomerates and sandstones with individual beds about 7 to 15 feet thick showing a total net pay of 65 feet. The lateral continuity of these bodies is extremely difficult to define. This lack of continuity and the oil characteristics (undersatured 28 °API with a GOR of 80 SCF/STB) most likely causes well production rates to decline rapidly in the first year of production. The development of this formation was based on vertical wells which only accumulate 57,000 bbl on average. Due to the high drilling costs and the low production obtained, they were not economic. The recommendation of the study team was to drill a pilot high deviated well (slanted) in order to add as many layers as possible increasing the net pay per well.