As the treatability of the syndrome of autism becomes more possible there is a great deal more interest in the effectiveness of various therapies. Although the very influential nonmedical literature cited in the Autism Research Review International Newsletter finds that dimethylglycine (DMG) is regarded as more effective than the usual psychopharmacologic drugs, there have been no studies of DMG using the currently accepted research methodology. We report a double-blind, placebo-controlled, crossover pilot study of low dose DMG and placebo in a sample of eight autistic males ranging in age from 4 years 5 months to 30 years 8 months, who completed the full 3 1/2-month study consisting of drug-free baseline periods at the beginning, end, and in-between two, 1-month double-blind trials in which DMG or placebo was given. Measures included the Campbell-NIMH rating scale, an experimental rating scale, and an individualized scale created for each child. Analysis of all three scales revealed no statistically significant differences, and parent reports were equally distributed. The major methodologic weaknesses of the study are thought to be the low dosage of DMG and the small sample size.