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An apparatus for high resolution photoelectron spectrometry of negative ions is described. With this machine, energy spectra of electrons detached from OH , SH , and SD-ions by 488.0 nm and 514.5 nm radiation have been measured with a resolution of 5-7 meV. The rotational branches have been clearly resolved and the electron angular distributions have been determined for the different branches. The measured rotational structure has been reproduced in model calculations; for SH-, our results confirm the threshold model of Walker. The following rotational constants for the respective negative ions have been derived: B0(OH-)=18.75(15)c m 1, B0(SH )=9.39(3)cm 1, B0(SD-)=4.87(2)cm-1The electron affinities of SH, SD have been determined to be EA(SH)=2.317(2)eV and E A(SD) = 2.315 (2)eV; the negative ion vibrational frequencies have been found to agree with those in the parent neutrals to within about 100 cm-1