This report describes a focused pilot study of the field measurement of lead in paint that has been performed with three objectives: (1) to evaluate the ability of previously performed laboratory experiments to predict measured field performance across a given field technology; (2) to identify sources and magnitudes of errors associated with the technologies that were researched; and (3) to provide a document that can serve as a guide to the field inspector or lead tester. To achieve these objectives, three different field technologies--portable X-ray fluorescence (XRF), a colorimetric field kit, and qualitative test kits--were evaluated in the field. Their performances were measured against analysis of paint samples performed using an established laboratory technique, microwave acid digestion/inductively coupled plasma emission spectrometry (MW/ICP). In summary, this report provides the tester/inspector with a clear indication that location to location concentration variability is the major source of uncertainty when using these three brands of XRFs to determine whether the lead on some component may exceed a given action level.