Background: Several case reports document successful treatment of sebaceous hyperplasia with the pulsed-dye laser. Moreover, noninvasive real-time confocal laser scanning microscopy elucidates the vascular nature of these lesions and their pathophysiologic response to treatment mediated by vessel coagulation. Methods: Ten patients with 29 lesions of sebaceous hyperplasia were treated with 3 stacked 5-mm pulses of the 585-nm pulsed-dye laser at fluences of 7 or 7.5 J/cm². Confocal imaging was performed before and immediately after treatment, as well as at 2, 4, and 8 weeks of follow-up. Results: The great majority of lesions responded to one treatment, with complete disappearance in 28%, decrease in diameter in 66%, and flattening in 93%. Although 28% recrudesced after initial involution, only 7% recurred completely. Three lesions became eroded or crusted, and 7 experienced cutaneous depressions before complete healing, but no scarring or pigmentary side effects were noted. Confocal imaging revealed a prominent “crown” of blood vessels surrounding the sebaceous duct and coagulation of these vessels with pulsed-dye laser treatment. However, the vessels reappeared during follow-up, and no noticeable morphologic changes in the sebaceous duct were noted. Conclusion: Vascular targeting of sebaceous hyperplasia can be monitored with real-time reflectance confocal microscopy. Most sebaceous hyperplasia regresses after one treatment with 3 stacked pulses of the 585-nm pulsed-dye laser. Whether this response is due to temporary ischemia induced by selective vessel destruction or nonspecific thermal diffusion beyond the vessels from pulse stacking has not been determined. (J Am Acad Dermatol 2000;43:49-53.)