This video describes a fornix based trabeculectomy with unexpected iris incarceration in a patient with elevated IOP (26 mmHg). A fornix based flap is created for a wide surface area for mitomycin. The size of the sutures, needles, and types of instruments used are described. Radial and post- cuts are shown in iris incarceration, as well as water tight closure techniques. Variations in fluid flow relating to the IOP is also discussed.