The DMP is a retail-level heroin purchase program designed to gauge the heroin market in major metropolitan areas. Data for the report were based on undercover heroin purchases, and subsequent in-depth chemical analyses, on the streets of the 23 cities included in the analysis. DEA officials in the sampled cities are tasked with making 10 street-level heroin purchases per quarter, except in New York City, where officials must make 20 purchases per quarter. Since its inception, the DMP has found that the purity of heroin continues to rise as the price continues to decline. Recent data also indicate that South American-produced heroin dominates the market east of the Mississippi River, while Mexican black tar and brown powder heroin dominate the market west of the Mississippi. Data from 2002 further indicate that nationwide samples of heroin have the highest average purity level compared with previous years. However, both the price and purity of heroin have remained relatively stable over the past several years. The report provides 2002 data for each of the 23 cities in the sample, as the heroin market tends to be unique in each metropolitan area and, as such, national averages and calculations are problematic and may be misleading. Information is provided on the price and purity of heroin in each city; comparisons between cities are made in some instances; and in some cases, numbers and cases of overdose deaths are reported. Appendices offer definitions and 2001 and 2002 heroin counts, purities, and prices in table format. Tables