This annual review of X- ray fluorescence covers developments over the period 2001-2002 in instrumentation and detectors, matrix correction and spectrum analysis software, X- ray optics and micro fluorescence, synchrotron XRF, TXRF and portable XRF as assessed from the published literature. The review also covers a survey of applications, including sample preparation, geological, environmental, archaeological, forensic, biological, clinical, thin films, chemical state and speciation studies. During the current review period, publications have demonstrated the elegant and ( almost) comprehensive description of a detector response model for Si( Li) detectors, matching theory with practice, by the Guelph group, and the continuing growth in use of EDXRF in place of WDXRF in a range of applications, particularly the analysis of environmental samples. A notable application, which is as much a comment on the state of society as on science, is the study of blood lead concentrations of gunshot victims. Finally, it is pleasing to note the increasing number of third generation synchrotron facilities becoming available, so extending the facilities for specialised XRF research.