Recent 2010 emissions standards for heavy-duty engines have established a limit of oxides of nitrogen (NOx) emissions of 0.20 g/bhp-hr. However, it is projected that even when the entire on-road fleet of heavy-duty vehicles operating in California is compliant with 2010 emission standards, the National Ambient Air Quality Standards (NAAQS) requirement for ambient particulate matter and Ozone will not be achieved without further reduction in NOx emissions. The California Air Resources Board (ARB) funded a research program to explore the feasibility of achieving 0.02 g/bhp-hr NOx emissions. This paper details engine and aftertreatment NOX management requirements and model based control considerations for achieving Ultra-Low NOX levels. Data will be presented for several Advanced Technology aftertreatment technologies and the integration of those technologies with the engine calibration. Further development is necessary for optimizing vocational test cycle emissions, but the results do demonstrate a potential pathway to achieving ultra-low NOX emissions on future heavy duty vehicles.