A single magnetic- and current-tuned PbSe diode laser was used to measure completely resolved spectra of SO2at low pressures over a major portion (1176.0-1265.8 cm-1) of the branch of the ν1band for the first time. It is shown that the combination of magnetic and current tuning allows complete coverage of this 89.8-cm-1wide spectral region. Results generally show excellent agreement with theoretically generated spectra. Magnetic-tuning rates and, with magnetic field applied, current-tuning rates were observed to be significantly nonlinear. Precise spectroscopic data could be obtained with these nonlinearities taken into account. The current-tuning rate in zero magnetic field was essentially constant over the range investigated.