The joint probability density function of the temperature &thgr; and its instantaneous dissipation &khgr; is important for the development of turbulent reacting flow models. Measurements are presented, in the nearly self‐preserving region of a turbulent plane jet, of the joint statistics of &thgr; and an approximation &khgr;1to &khgr;. Properties of the three, separately obtained, dissipation components are first compared to justify the choice of &khgr;1. The quantity chosen is an appropriately weighted linear combination of the squared values of the temporal derivative, shown to be an adequate substitution for the derivative in the streamwise direction, and the derivative, in either the lateral or spanwise directions, of temperature. The correlation between &thgr; and &khgr;1is weak, receiving contributions primarily at small frequencies. The assumption of independence between &thgr; and &khgr;1, allowing the joint probability density function of these two quantities to be written as a product of the individual probability density functions, improves with distance from the jet centerline.