A detailed examination of the ground and first excited singlet electronic states of HSiBr has been carried out through analysis of the 500-400 nm band system, using pulsed discharge jet and laser-induced fluorescence techniques. HSiBr and DSiBr have been produced by an electric discharge through SiHBr3 and SiDBr3 vapor in argon. Rotational analysis of the 0(0)(0) bands yielded the structural parameters r(0) "(SiH) = 1.518(1) Angstrom, r(0) "(SiBr) = 2.237(1) Angstrom, theta(0) " = 93.4(3)degrees, r(0)’(SiH) = 1.497(10) Angstrom, r(0) "(SiBr) = 2.208(2) Angstrom, and theta(0)’ = 116.4(7)degrees. Previous anomalies in the geometric parameters and vibrational frequencies have been resolved and the ground state bond lengths and vibrational frequencies are found to be comparable to those of SiH and SiBr. Harmonic force fields have been determined for the ground and excited states and the radiative Lifetime of HSiBr has been measured to be 598 +/- 18 ns.