The Tropospheric Emissions, Monitoring of Pollution (TEMPO) program was selected by NASA for the Earth Venture Instruments 2012 Announcement of Opportunity.  TEMPO is an innovative use of a well-proven remote sensing technique for air quality measurements and Ball Aerospace is the instrument developer.  Low Earth Orbit (LEO) remote sensing techniques have made measurements of photochemical species, precursors and oxidation products relative to air quality.  These include NO2, O3, SO2, C2H2O2, CH2O and atmospheric aerosol.  The TEMPO instrument combines a high spatial resolution spectrometer with a geostationary orbit to achieve unprecedented spatial and temporal measurement resolution. These new measurements will allow for hourly observations of air quality of Greater North America with urban-regional spatial scales (<60 km2).  Hourly daytime observations will allow for measurements of the complex diurnal cycle of pollution driven by photochemistry.  These measurements will contribute to better understanding of regional air quality and improved air quality forecasts.  The TEMPO mission will be hosted on a yet to be announced commercial communications satellite with a launch date no earlier than 2020.  In this paper, we discuss the mission and instrument design, as well as the opportunities and challenges involved in a hosted payload.