Implementations of smart-field strategies with intelligent completions, i.e., interval control valves and interval control devices, are growing in the oil industry. Yet, there is still resistance by some companies because of concerns for (1) provable long-term value in terms of oil recovery and returns; (2) risk of valve failures affecting well integrity and performance; (3) lower returns of actual results relative to predicted results (i.e., overoptimistic projections, often from simulation); and (4) uncertainty as to the most effective future operational practices. This paper presents a systematic analysis of well rates and pressures as predicted by simulation for a long horizontal well. The paper investigates long-term value, analyzes impact of valve failure on production, provides estimates on the impact of reservoir uncertainty on performance, and demonstrates production improvements from effective operational control procedures for the horizontal well, for a multi-lateral well, and for a 20-production well waterflood. The paper validates and implements a methodology using simulation-based analysis and automated procedures to optimize valvecontrol strategies: oil production is maximized, while water production is better managed. Two control strategies are investigated and compared against a do-nothing approach: a fixed control strategy and a flexible control strategy.