We made small nonrhegmatogenous retinal detachments (blebs) in rabbits over regions of retinal pigment epithelium (RPE) that were damaged mechanically or by laser photocoagulation. Fluorescein diffused readily into blebs made over damaged RPE, but the subretinal fluid was resorbed more quickly than from blebs overlying normal RPE. Thus, focal damage appears to facilitate water movement from, rather than into, the subretinal space. We conclude from these data that central serous chorioretinopathy is not caused simply by a passive "leak" through the RPE barrier, and the effects of photocoagulation in this disease cannot be explained simply as sealing such a leak.