In a study to evaluate the drug treatment and aftercare efforts sponsored by the State Department's International Narcotics and Law Enforcement Affairs Bureau, residential Therapeutic Community (TC) treatment programs in three Latin American countries--Brazil, Peru and Argentina--were examined to identify promising practices and to assess lessons learned. Based on field visits, in-person interviews, focus groups, and document analyses, the authors recommend the following promising practices for replication: (1) Effective outreach and media strategies; (2) Tailored activities addressing local needs; (3) Emphasis on client development; (4) Focus on including the family as a unit; (5) Recruitment and retention of motivated volunteers; (6) Commitment of staff members.