The first program evaluated herein adopted an action research approach, and the second adopted a structured community development approach. The two strategies reflected different assumptions and different opportunities for action. Both teams made considerable progress, and both were successful in changing ways of approaching drug policy and practice. Drug prevention was placed firmly on the local agenda and local groups are working together to tackle the problem. Their main aims could be said to have been achieved in that they made an impact; they encouraged some collaboration; and they involved a multiplicity of agencies, some of them new to community participation. The key point that emerges from the comparative study is the importance of being knowledgeable about the complexity of local conditions and sensitive to matters relating to this. The key factor which affects what happens is the shape and nature of existing networks in a locality. Footnotes, tables, figures, appendixes, references