The technique of H Rydberg atom photofragment translational spectroscopy has been applied to a high resolution study of the primary photochemistry of methanethiol (CH3SH) following excitation at a wide range of wavelengths in the near ultraviolet. In accord with previous studies of this molecule, excitation within its first (1 (1)A"-($) over tilde X(1)A’) absorption continuum is shown to result in S-H bond fission. Spectral analysis yields a refined value for the bond dissociation energy : D-0(0)(CH3S-H)=30 250+/-100 cm(-1). The resulting CH3S(($) over tilde X) fragments are deduced to carry only modest vibrational excitation, distributed specifically in the nu(3) (C-S stretching) mode and in one other mode having a wave number of similar to 1040 cm(-1). We associate this latter mode with bending of the CH3 moiety in the plane containing the C and S nuclei and the lobe of the unpaired electron which was originally involved in the S-H bond. Decreasing the excitation wavelength (while remaining within the first absorption continuum) results in an increase in both the vibrational and rotational excitation of the CH3S(($) over tilde X) fragments, but a decrease in the relative yield of the upper ((2)E(1/2)) spin-orbit component. Excitation at still shorter excitation wavelengths accesses the second (2 (1)A"-($) over tilde X(1)A’) absorption band of CH3SH. The CH3S fragments resulting from S-H bond fission at these excitation wavelengths are observed to carry very much higher levels of vibrational excitation in the above two modes. The observation of H atoms attributable to secondary photolysis of SH(X) fragments indicates increased competition from the alternative C-S bond fission channel at these shorter excitation wavelengths. Additional peaks in the H atom time-of-flight spectrum, most clearly evident following excitation at wavelengths in the range 213-220 nm, are interpretable in terms of secondary photolysis of the primary CH3S(($) over tilde X) fragments yielding thioformaldehyde (H2CS), primarily in its ($) over tilde A(1)A(2) excited electronic state. Symmetry arguments provide an explanation for this specific electronic branching in the near ultraviolet photolysis of CH3S fragments.