Set to tame chaotic growth in Lower Manhattan, the 1811 Commissioner’s Grid has proven resilient in it’s ability to organize urban form. The grid’s multiple transformations – portions removed, setbacks, scale change, and hybridization – illustrate its overall versatility. Now, two hundred years later, New York City faces new and unprecedented challenges. Aging infrastructure, increased consumption, and a growing population are testing limits on multiple systems. extruded Grid proposes the next logical step to the grids narrative – extend it downward. extruded GRID redefines Manhattan with seven, north-south and eight, east-west corridors below city streets. These corridors organize and upgrade infrastructure such as transportation, power, water, gas, steam, waste, parking, storage, waste, and other surface utilities, while providing flexibility for future change. Divided into three zones – public space, transportation, and utilities – the corridors create efficiency and free up valuabe real estate. extruded GRID capitalizes on New York’s infrastructure, seeing it as the last urban layer yet to be designed beyond functionality.