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The decision whether a contact lens is to be used on a daily or extended wear basis is made by the contact lens provider (such as a physician) as opposed to the manufacturer of the lens. There is currently confusion regarding the physical characteristics of disposable contact lenses. Disposable contact lenses are hydrogel plastics molded into designs similar to, but less expensive than, those previously used for extended wear contact lenses. A study was undertaken to determine if the oxygen permeability of these disposable lenses was changed by the new, less expensive production method. Oxygen permeability, the intrinsic ability of a material to transmit oxygen by diffusion, is an important feature of modern contact lens material. A change in oxygen permeability could put stress on the cornea (transparent covering of the eyeball) due to decreased exposure to oxygen. Three brands of disposable contact lenses were evaluated using a method which has been the industry standard for many years (single-chamber polarographic oxygen permeability). The three brands evaluated were Acuvue, NewVues, and SeeQuence. The results showed that the inexpensive production method, permitting the low per unit cost of the lenses, does not change the physical properties of oxygen permeability or transmissibility (ability of a lens of a specific thickness to transmit oxygen by diffusion). It is concluded that the stress to the cornea is similar when either disposable lenses or conventional reusable lenses are worn. (Consumer Summary produced by Reliance Medical Information, Inc.)