Eye Movement Desensitization and Reprocessing (EMDR) was one of the first treatments of posttraumatic stress disorder (PTSD) to be evaluated in controlled research and has to date been empirically supported by 13 such studies. This article reviews the historical context and empirical research of EMDR over the past dozen years. Historically, EMDR's name has caused confusion in that “desensitization” is considered to be only a by-product of reprocessing and because the eye movement component of EMDR is only one form of dual stimulation to be successfully used in this integrative approach. Research is needed to determine the comparative efficacy of EMDR relative to cognitive-behavioral treatments of PTSD. However, this has been hampered by the lack of independent replication studies of the latter treatments. Current component analyses of EMDR have failed to effectively evaluate the relative weighting of its procedures. Parameters for future research and the testing of protocols for diverse disorders are suggested. © 2002 John Wiley & Sons, Inc. J Clin Psychol 58: 1–22, 2002.