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 countries in Southeast Asia--Malaysia, Singapore, and Thailand--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) structured treatment environment tailored to meet cultural norms; (2) successful collaboration among training networks and agencies; (3) utilization of an active volunteer community; (4) inclusion of vocational training to facilitate successful reintegration; (5) use of religion to enhance treatment resident growth; (6) inclusion of family in the treatment process; and (7) establishment of a systematic program re-entry process. (Contains 3 tables.)