This clinical trial will compare 10 week treatment with acamprosate (2 gr/day) versus placebo, combined with weekly abstinence oriented individual counseling, in methamphetamine dependent patients, 72 subjects will be enrolled, with an interim analysis scheduled after 36 enrolled. Primary outcome is methamphetamine absitience over the 10 week treatment period, and the last 2 weeks of treatment. Abstinence is defined on a weekly basis as no urine positive of methamphetamine (or amphetamine) and self-report of not use for the 7 day period. Secondary measures include treatment retention, drug craving, mood, and safety.