Abstract: Reports on cases of alleged drug-facilitated sexual assault (DFSA) have increased since the mid-1990s. The aim of this study was to identify the extent and types of drugs found in cases of alleged sexual assault (DFSA) in the Netherlands. In total, 135 cases of alleged DFSA were identified. Most of the victims were women (94%), and the mean age of the victims was 25 years. Blood and urine samples were tested for the presence of alcohol, drugs (drugs of abuse and prescription drugs), or both. In 27% of the cases, no alcohol and/or drugs were found. With increasing time delay, more cases were found to be negative. Alcohol is the most commonly found drug followed by nonopiate analgesics, illicit drugs, and benzodiazepines. In some cases, the absence of alcohol and drugs may represent false-negative results owing to the time delay between alleged sexual assault and sampling.