Photometry and spectroscopy of the unique pre-main-sequence eclipsing objec
t KH 15D in the young cluster NGC 2264 are presented. The orbital period is
48.34 days, and both the length (similar to 16 days) and depth (similar to
3 mag) of the eclipse have increased with time. A brightening near the time
of central eclipse is confirmed in the recent data but at a much smaller a
mplitude than was originally seen. Spectra taken when the star is bright sh
ow that the primary is a weak T Tauri star of spectral type K7. During ecli
pse there is no detectable change in spectral type or reddening, indicating
that the obscuration is caused by rather large dust grains and/or macrosco
pic objects. Evidently, the star is eclipsed by an extended feature in its
circumstellar disk orbiting with a semimajor axis of similar to0.2 AU. Cont
inued photometric monitoring should allow us to probe the disk structure wi
th a spatial resolution of similar to3 x 10(6) km or better.