Accessing and producing the Gulf of Mexico’s Lower Tertiary and other ultradeepwater plays require aggressive reservoir stimulation and a downhole infrastructure capable of supporting decades of high production rates in extreme environments. The Baker Hughes Hammerhead system is the industry’s first wellhead-to-reservoir integrated completion and production solution specifically designed and tested for ultradeepwater conditions. Built to withstand pressures and temperatures up to 22,500 psi and 300°F, the system is capable of handling sustained flow rates up to 30,000 B/D with high differential pressures up to 15,000 psi for maximum reservoir drainage. The system’s high-performance frac-pack solution can deliver massive stimulation treatments into as many as five zones in a single trip. Surveillance and control capabilities enable remote monitoring and selective zonal control with dual-choking, hydraulic intelligent-well-system valves. Electric pressure and temperature gauges and fiber-optic distributed-temperature sensing in the lower completion provide continuous data so production can be optimized on the fly. Deposition inhibitor technology can be delivered as needed through chemical-injection valves, helping to avoid costly production interruptions and to provide reliable flow assurance for the life of the well. With the integrated system, operators will be able to reliably access Lower Tertiary reservoirs and maintain long-term production, safely and reliably, for full-field economic payback.