The GAITRite is a portable gait analysis tool for automated measurement of spatiotemporal gait parameters. Although frequently used for clinical and research purposes, the concurrent validity of GAITRite has not been validated against a criterion measure. The aim of this experiment was to investigate the concurrent validity and test retest reliability of the GAITRite carpet walkway system for quantification of spatial and temporal parameters of the footstep pattern. Twenty-five healthy adults aged 21-71 years (mean 40.5 years, S.D. 17.2) performed three walk trials at self-selected pace, three at fast pace and three at slow pace. For each trial, data were simultaneously collected from the GAITRite and a Clinical Stride Analyzer, which has established reliability and validity. At preferred, slow and fast walking pace there were very high correlations between the two measurement systems for gait speed (ICC (2,1)=0.99), stride length (ICC (2,1)=0.99) and cadence (ICC (2,1)=0.99). Correlations between the electronic carpet and the stride analyser were moderate to high for single limb support (SLS) time (ICC (2,1)=0.69-0.91) and weak for the proportion of the gait cycle spent in double limb support (ICC (2,1)=0.44-0.57). The reliability of repeated measures for the GAITRite was good at preferred and fast speed for speed (ICC (3,1)=0.93-0.94), cadence (ICC (3,1)=0.92-0.94), stride length (ICC (3,1)=0.97), single support (ICC (3,1)=0.85-0.93) and the proportion of the gait cycle spent in double limb support (ICC (3,1)=0.89-0.92). The repeatability of the GAITRite measures were more variable at slow speed (ICC (3,1)=0.76-0.91). These results indicate that the GAITRite system has strong concurrent validity and test retest reliability, in addition to being a portable, simple clinical tool for the objective assessment of gait.