Clinical Evaluation of the Causes of Contact Lens Related Dry Eye

Inclusion Criteria: * Reports late-day dryness symptoms with contact lens wear on questionnaire. * Wears FDA Group 2 hydrogel, FDA Group 4 hydrogel, or silicone hydrogel lenses. * Consistently uses either polyhexamethylene biguanide (PHMB) or polyquaternium-1 (PQT) contact lens care products (i.e. \>6 months including 1 month immediately before enrollment). * Other protocol-defined inclusion criteria may apply. Exclusion Criteria: * Wears daily disposable contact lenses. * Has significant symptoms related to lens fit or lens deposits. * Requires concurrent ocular medication (rewetting drops allowed). * Has used Restasis® in the last 3 months. * Wears punctal plugs fitted in the last 30 days. * Has any current systemic or ocular abnormality, infection or disease. * Uses any current systemic medication likely to affect tear film, e.g. antihistamines, betaadrenergic blockers, steroids. * Has a history of refractive surgery. * Other protocol-defined exclusion criteria may apply.