Solar and geomagnetic indices are described for use in the Jacchia-Bowman 2008 thermospheric density model (JB2008). The NRLMSIS-2000 model uses a sub- set of these indices and this discussion is applicable to that model as well. There are four solar and two geomagnetic indices used by JB2008. The F10.7, S10.7, M10.7, and Y10.7 solar indices are formed using the JB2006 methodology and they map energy from specific solar irradiance sources to major thermospheric layers. Energy that is deposited to the lower thermosphere and mesopause (85-100 km) is now provided. These solar proxies and indices are compliant with the ISO International Standard 21348 for determining solar irradiances. Reference values of the solar indices and proxies for short-term, intermediate-term, solar cycle, and 25-year periods from so- lar cycle 23 examples are provided for users who want reference values for planning and tests. The ap geomagnetic and Dst ring current indices are used in a two-index formulation that captures both low/unsettled activity and substorms/storms to represent changes to the neutral thermospheric densities as a result of high-latitude Joule heating and charged particle precipitation. The storm effects change the rate of exospheric temperature change, dTc, which affects satellite orbits. Reference values for ap, Dst, and dTc are provided using an example storm of November 20-21, 2003 for users who want reference values for planning and tests. Use of these solar, geo- magnetic, and ring current indices in the JB2008 model produces significant im- provements in empirical thermospheric density modeling. JB2008 provides stan- dard deviations of approximately 9–10% at 400 km, which is a significant decrease from 16% previously obtained using the Jacchia 70 model.