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Massive young stellar objects (YSOs), like low-mass YSOs, appear to besurrounded by optically thick envelopes and/or disks and have regions, oftenbipolar, that are seen in polarized scattered light at near-infraredwavelengths. We are using the 0.2'' spatial resolution of NICMOS on HubbleSpace Telescope to examine the structure of the disks and outflow regions ofmassive YSOs in star-forming regions within a few kpc of the Sun. Here wereport on 2 micron polarimetry of NGC 6334 V and S255 IRS1. NGC 6334 V consistsof a double-lobed bright reflection nebula seen against a dark region, probablyan optically thick molecular cloud. Our polarization measurements show that theilluminating star lies ~ 2'' south of the line connecting the two lobes; we donot detect this star at 2 micron, but there are a small radio source and amid-infrared source at this location. S255 IRS1 consists of two YSOs (NIRS1 andNIRS3) with overlapping scattered light lobes and luminosities corresponding toearly B stars. Included in IRS1 is a cluster of stars from whose polarizationwe determine the local magnetic field direction. Neither YSO has its scatteredlight lobes aligned with this magnetic field. The line connecting the scatteredlight lobes of NIRS1 is twisted symmetrically around the star; the bestexplanation is that the star is part of a close binary and the outflow axis ofNIRS1 is precessing as a result of non-coplanar disk and orbit. The star NIRS3is also offset from the line connecting its two scattered light lobes. Wesuggest that all three YSOs show evidence of episodic ejection of material asthey accrete from dense, optically thick envelopes.

Hubble Space Telescope NICMOS Polarization Observations of Three Edge-on Massive YSOs