The basis for the temperature dependence of the principal performance parameters of single and multi-junction concentrator solar cells is examined, focusing on the impact of bandgap and irradiance. The analysis of cells in the radiative limit establishes fundamental bounds. A quasi-empirical model yields predictions consistent with available data. A simple method for estimating the temperature coefficients of key performance parameters is identified. The degree to which the efficiency penalty associated with cell heating can be mitigated by high irradiance is also evaluated. Copyright © 2012 John Wiley & Sons, Ltd.