This field study evaluates the impact of replacing existing 17-inch Cathode Ray Tube (CRT) monitors with 19 and 21-inch CRT monitors and 18.1-inch Flat Panel Displays (FPDs) on matrices of productivity, visual comfort, and physical discomfort among 30 employees within a large insurance company (Policy Service and Claims). Metrics were analyzed over a five (5) month period. During Phase One (initial eight weeks) of the study, metrics were gathered weekly on 17-inch CRT monitors to establish a baseline of data on productivity, visual comfort and physical discomfort. During Phase Two (12 weeks), each subject used the 19-inch CRT, 21-inch CRT and 18.1-inch FPD for two weeks, respectively interspersed with other subjects in the study utilizing 17-inch monitors for the same time period. Initially, it appears that the 19-inch monitor enables users to enter more keystrokes per hour ( x19 =1894) than its 17-inch counterpart ( x17=1721) which would be a productivity enhancement. However, this value is not statistically significant (p>0.34). Analysis of additional performance metrics yielded similar results (p>0.2). The users’ level of visual comfort increased with all test display units over their existing 17-inch counterpart (p<0.023), but the data was not meaningful due to the minute difference between their mean values (&#8710;<0.75). Physical discomfort metrics were analyzed among all of the monitor treatments. Most employees were relatively comfortable through the duration of the study. Mean values across all physical discomfort metrics measured were less than one on a Borg scale of zero to ten, but none of the values among treatments were significant (p>0.31). Anecdotally, the users preferred the larger monitors.