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Effective zonal isolation within a layered reservoir in the Gulf of Mexico is a necessity to meet regulations for stacked reservoirs and to maximize total recoverables. Effective zonal isolation also ensures maximum production is achieved via a high-pressure proppant fracture treatment. A primary cement operation of a 10 1/8" production liner (within a 12 ¼" drilled hole section) was challenging due to a combination of high equivalent circulation density (ECD) and potential losses across a layered GOM reservoir. One layer had potential and significant depletion up to 8,000 psi. Critical well parameter considerations were: maintaining the liner burst of 18,200 psi, maximizing rotation and reciprocation capability of the liner, minimizing the impact on circulation and ECD, and ensuring compatibility with the mud systems. Following careful job planning, including the analysis of caliper data from logging while drilling (LWD) for the optimum placement, two metal expandable packers (MEPs) were installed on the 10 1/8" liner. The MEPs were positioned to straddle the highly depleted layer (one above and one below) in the 12 ¼" open hole section. The liner was deployed, and the cement operation was executed with minimal ECD impact from the inclusion of the MEPs. Surface pressure was applied to create sufficient differential pressure across the 10 1/8" liner wall to hydraulically expand the MEPs quickly under full surface control. This paper covers the qualification, planning, and deployment of MEPs to provide cement assurance (CA) for zonal isolation and improve the effectiveness of contingency cement squeezes. Though this technology has been used in other regions for several years, this was the first deployment in the Gulf of Mexico (GOM). The solution improved the probability of success of the primary cement job, negating the requirement for a remedial cement squeeze. The decision to run MEPs was based on the estimated cost savings of 3.5 million USD for remedial squeeze operations, a value proposition that did not account for the net present value (NPV) gain, due to improved fracture placement, compared to the case of poor cement isolation.