The program began in August 1990 and has become part of a community-based drug control strategy that targets buildings that are sites for drug trafficking or the sale of drug paraphernalia. Neighborhood groups, police, and other government agencies contact the program to make it aware of such nuisances. The NNAU uses three strategies: voluntary abatement, prosecutorial abatement, and community outreach. An analysis of the processing of a random sample of typical NNAU cases revealed that the majority of cases originated from the CCSAO drug prosecutions and that the most common action taken by the NNAU was to send a letter to the property owners advising them that a nuisance existed and warning them of the consequences if the situation was not corrected. The evaluation focused on the NNAU's effects on residents' perceptions and on subsequent drug dealing. Results of a survey of residents living on blocks with and without abatement actions produced no evidence that evictions had any impact on citizens' perceptions of drug activity, other signs of disorder, or feelings of safety on the block. Follow-up observations revealed no signs of drug dealing at 8 of the 10 abated buildings studied or on the blocks on which they were located. Findings indicated that abatement may sometimes slow or stop drug sales by targeted individuals, but the small sample size points to the need for further research. Tables, notes, and 23 references (Author abstract modified)