We attempted to seal 15 consecutive filtering bleb leaks in 11 patients using argon laser energy. Eight leaks were at the conjunctival-corneal interface associated with a fornix-based flap, 4 leaks resulted from suture scissoring of the conjunctiva, and 3 leaks were button-holes in the conjunctiva. Thirteen leaks occurred within 2 weeks after filtering surgery, while 2 were of late onset. Argon laser parameters used were a 500-microns spot size, 0.1-s time interval, and between 500 and 1800 mW of power. Thirteen leaks were sealed after one or two laser sessions, while 2 leaks required other treatment modalities. Complications included conjunctival fenestration and transient corneal stromal opacities. This study suggests that the argon laser can be used to seal filtering bleb leaks in many patients following filtering surgery.