Abstract
We present high resolution BIMA polarization observations of the star forming region NGC 7538 IRS1. At 230 GHz, we detect polarization above the 3-sigma level toward five independent points in the source. The polarization angles appear to be similar in the eastern and western parts of the source, then rotate around by about 90 degrees toward the central region of the source. We examine various models of magnetic field morphology that could give rise to such a configuration. Also, the polarization decreases with increasing intensity toward the central region of the source, likely indicating that the dust polarization efficiency decreases toward higher density regions in the source.