"Methamphetamine has 'exploded' from 'a West Coast biker drug' into America's heartland and could replace cocaine as the Nation's primary drug threat." In an effort to explore the dynamics of meth production, distribution, and use, the San Diego Association of Governments used the Arrestee Drug Abuse Monitoring program to research methamphetamine use and its consequences among arrestees. This Research Report, Meth Matters: Report on Methamphetamine Users in Five Western Cities, describes the results of interviews with persons arrested and booked into detention facilities in five cities: Los Angeles, San Diego, and San Jose in California; Phoenix, Arizona; and Portland, Oregon. The findings suggest that the production and use patterns of meth are different from those of other illegal drugs. These differences have policy implications for prevention, intervention, and control strategies.