An evaluation of the hand-held portable Lactate Pro Analyser (KDK) was undertaken to assess its accuracy, reliability and versatility. Capillary blood samples were drawn from elite athletes in both laboratory and field settings and analysed in parallel. Accuracy was determined in relation to three other lactate analysers: (1) the ABL 700 Series Acid-Base analyser (n = 172 cases), (2) the Accusport Lactate Meter (n = 118 cases), and (3) the YSI 2300 Stat lactate analyser (n = 22 cases). The level of agreement was determined over the range of 1-18 mM. The repeatability of results between two different Lactate Pro analysers was also determined over the same range. Versatility was assessed in the field, where the Lactate Pro was used with elite athletes under a range of outdoor and indoor testing conditions. The correlations between the Lactate Pro and the ABL 700 Series Acid-Base analyser, YSI 2300 and Accusport were r = 0.98, r = 0.99, r = 0.97. The correlation between the two Lactate Pro analysers on the same sample (n = 96 cases) was r = 0.99. The level of agreement between the Lactate Pro and other analysers was generally less than +/- 2.0 mM over the physiological range of 1.0-18.0 mM (range of mean difference: -0.06 mM to 0.52 mM). The Lactate Pro was easy to operate and successfully completed the sample analysis in 100% of the tests performed. In summary, the Lactate Pro is accurate, reliable and exhibits a high degree of agreement with other lactate analysers.