The laser emission of vibrationally excited OH in the electronic ground state, produced in pulsed electric discharges through O3&sngbnd;H2gas mixtures, has been studied using two transverse discharge systems. Discharges were produced in two electrode and multipin transverse configurations. Stimulated emission between the &ngr; = 3→&ngr; = 2 and &ngr; = 2→&ngr; = 1 levels was observed in the 3 &mgr; wavelength region. The output has been investigated as a function of composition and pressure of O3&sngbnd;H2mixtures, addition of foreign gases, and discharge energy. Output intensities were compared to that of the HF laser emission produced from H2&sngbnd;SF6in the same discharge system. The two discharge configurations gave similar intensities; this OH laser was shown to have approximately 10−2times the power of the HF†laser.