Abstract
We briefly review the properties of the most luminous submillimeter galaxies identified by SCUBA. We illustrate the main points with a description of the recently discovered submillimeter source, SMM J09431+4700, a z = 3.35 hyperluminous infrared galaxy which hosts an obscured AGN. We compare the properties of this galaxy with the only other well-studied hyperluminous galaxy identified by SCUBA surveys - the z = 2.80 BAL-QSO SMM J02399-0136. The similarity of the properties of these two systems suggests that feedback from AGN is important in regulating the evolution of the most luminous starbursts in the early Universe.
