The findings revealed that mid- and low-level PSUs (as derived from police data) often had a high number of self-reported powder cocaine and heroin users and sellers. They suggested that NYPD data corresponded most accurately with self-report data on crack sales and use, but tended to underestimate the use and sale of powder cocaine and heroin. The authors suggest that this may be because of the increased visibility of crack use and sales as compared to heroin or powder cocaine and to NYPD policies targeting the crack market. Research methodology involved dividing Central Harlem into 45 primary sampling units (PSUs) and dividing 2 years of NYPD data into 3 strata based on the level of drug-allegations, low, mid, or high. Self-reported drug use and sale data were gathered via interviews with 657 participants who were recruited within the PSUs through chain referral sampling. The analysis compared the self-report data and the NYPD datasets from nine of the randomly selected PSUs in the three strata. Policy implications are discussed and revolve around the dilemma of responding to crimes that cause the most public outcry or responding equally to all crimes across all geographic areas. Tables, references