The strong correlations between supermassive black hole mass and host galaxy bulge properties imply a physical mechanism for mediating the growth of both structures. Quasar disk winds are likely to be important in this process. These outflows are most readily observed in the ~20% of quasars with broad absorption lines, where the observer's line of sight passes through the wind. Until fairly recently, the paucity of X-rays from these objects was notable, but current sensitive hard-band missions such as Chandra and XMM-Newton are routinely detecting them and providing new information on the nature of the outflows. X-ray studies of quasar samples chosen by ultraviolet emission-line features are providing additional information on generic wind properties as well as the effects of orientation on multiwavelength phenomenology. These new insights set important constraints for theoretical modeling of quasar outflows.