In long horizontal wells, oil production rate is typically affected by the reservoir heterogenities, heel to toe effect and mobility ratio. The resulting imbalanced production profile may cause early water or gas breakthrough into the wellbore. Once coning occurs, well fluid production may be severely decreased due to limited flow contribution from the toe or from reservoir areas with high flow resistance in the porous media. To eliminate this imbalance, passive inflow control devices (PICDs) are placed in each screen joint or inflow point to balance the production influx profile across the entire lateral length and compensate for permeability variation.PICD performance in producer (oil, gas, and high gas/oil ratio environments) wells under different operational conditions will be presented to show the technical benefits of this technique as well as their improved recovery efficiencies when compared to non-PICD completions. Fluid viscosity insensitivity of the PICD is critical to minimize preferential water flow whenever water breaks through into the well. The quantification of the benefits of this completion technique was performed using a fully integrated reservoir simulator where the PICD flow performance characteristic (as a function of fluid properties and geometry), well completion description (packers, blank pipe, gravel pack, annulus flow, etc.) and reservoir simulation are considered. Shutting off whole sections that have unacceptably high water and/or gas production using the latest PICD feature is also modeled to show improved recovery performance. This paper details the development of the latest-generation PICD design concept. Because these PICDs are permanent downhole components, their long-term reliability is imperative, and these new developments will improve their resistance to erosion and their ability to effectively balance inflow. Computational flow dynamics (CFD) analysis was used extensively to characterize the new design, under liquid and gas conditions, along with actual full-scale flow testing.