OBJECTIVES: This study was performed to examine the psychometric performance of the four VISTAS-18 scales (i.e., Near Function, Intermediate Function, Extended-Intermediate Function, Distant Function) to the known benefits of intraocular lens (IOL) surgery, and more subtle differences between monofocal and multifocal IOL types.  METHODS: Subjects (Ss) were recruited from surgery clinics 2-8 weeks prior to receiving bilateral IOL implants. Visual assessments were conducted at the pre-surgical visit and then after recovery.  Following both visits, Ss completed a self-report questionnaire and the VISTAS item pool. The four VISTAS-18 Function Scale scores were evaluated using change from baseline in visual acuity assessments, and as well the type of IOL implant.  Responder analyses were conducted for each distance range.  RESULTS: Ss (n=61) had a mean age of 69.0 years (SD= 9.5) were in good health prior to surgery, although with low satisfaction with their vision and very low satisfaction with their visual aids.  Most Ss received monofocal (n=39) or multifocal (n=16) lenses.  Uncorrected and corrected visual function improved significantly following surgery on all four VISTAS-18 scales.  Greater improvements were observed on the Near (p=0.007) and Intermediate (p=0.017) Function Scales for recipients of multifocal versus monofocal lens.  The responder analyses indicated that 10/15 (66%) individuals who received multifocal lenses reported a one or more point reduction in near range task difficulty, and 11/15 (73%) in the intermediate range, compared to only 10/35 (29%) and 16/30 (53%) of individuals receiving monofocal implants.  CONCLUSIONS: The VISTAS-18 Function Scales performed well, both in terms of changes in visual acuity associated with IOL implantation, as well as in demonstration of responsiveness to more subtle differences in Near and Intermediate function associated with lens type.  The clinical implications of reliable assessment of visual tasks in near, intermediate and distant ranges of vision are discussed.