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In atmospheric pressure combustion environments, the measurement of OH rotational temperature form laser fluorescence has been complicate by problems encountered with fluorescence trapping, nonequilibrium excited state populations, sensitivity to the spectral bandwidth of the detection system and quenching effects. In this work a two-line laser fluorescence technique is described for the measurement of the OH rotational temperature which eliminates the above problems. The technique consists of exciting a specific rotational level in the $A2\Sigma (v\prime =0)$ state from two different rotational levels in the $X2\pi (v\prime \prime =0)$ ground state, using satellite transitions, and monitoring the broad band fluorescence. This approach is similar to a two-line atomic florescence temperature measurement, but applied to a molecular system. Examples of the application of the technique in flames will presented.