A group of self-acknowledged past MDMA users, participants in a tryptophan challenge test, were evaluated for a number of possible neuropsychological deficits in a battery of tests. There were no indications of deficit, although some mild memory impairment was suggested. This was felt to be inconsequential (the volunteers that just recently flown some distances to participate in the tests, and the only documented drug common to all subjects was the intentionally administered tryptophan. The conclusions, nonetheless, are framed to raise concerns about the possible detrimental effects of MDMA use.