This paper specifically addresses strategies used by harm reduction organizations and by users to ascertain the contents of ecstasy tablets, and considers whether these strategies are adequate means of detecting fake or adulterated pills and reporting variations in dosage. After briefly discussing the effects and risks of ecstasy, the author reports that shortly after being scheduled, the ecstasy tablets changed both in dosage and in presence of MDMA. Harm reduction organizations offer a number of different ways for ecstasy users to determine pill contents, including submitting pills for laboratory analysis and providing users with Òtest kitsÓ containing Marquis reagent or other simple tests. Examination of laboratory analyses of ecstasy pills indicates that approximately 60% of materials submitted contain MDMA or a closely related drug (e.g. MDA, MDE), approximately 30% contained other drugs instead of substituted amphetamines, and some pills contained both MDMA and other drugs (such as caffeine or ketamine). The author notes that both laboratory pill testing and home testing kids fail to address issues of dosage variation, and so people might still take more ecstasy than they intended if using an unknown ÒbrandÓ found to contain MDMA, or if the dosage contained in a known brand changes over time. The author also argues that test kit results may not be accurate when performed at clubs, since conditions needed for an accurate reading of test results, such as white light or a white ceramic plate, are unlikely to exist at a club or rave setting. The author notes that methods using infrared spectrometry are more accurate than test kits, but potential heterogeneity of pill contents may require that the pill be crushed to provide the most accurate result. The author ends his essay by concluding that home test kits and laboratory testing are not sufficiently accurate and specific enough to reduce the risks of using fake or adulterated pills. The author does not fully explain why better tests of ecstasy contents, such as those employing spectroscopy, would not provide adequate information to ecstasy users.