This is the fourth bulletin in the series of annual bulletins on the Alcohol and Other Drug Treatment Services National Minimum Data Set (AODTS-NMDS). The AODTS-NMDS aims to provide ongoing information on the demographics of clients who use these services, the treatment they receive and administrative information about the agencies that provide alcohol and other drug treatment. The data contained in this bulletin are derived from the comprehensive AODTS-NMDS 2003-04 annual report.