Significant health and social benefits may result from a reduction in the prevalence of injecting, the frequency of injecting, or both even when the aggregate numbers of illicit drug users remain constant. However, reducing injecting rather than reducing drug use has received little attention to date. Two distinct points for route transition intervention include preventing injecting among existing non-injecting drug users and promoting the transition away from injecting among current injectors. The development of route transition interventions has implications for both basic research and program evaluation. The basic research tasks involve developing a better understanding of the impact of using different drug delivery systems. In addition, good process evaluations should take place before it is reasonable to seek outcome data. The benefits of more finely focused policies that aim to reduce harm by reducing the level of injecting are likely to include health improvements in individual drug users, improved public health, and safer communities. Figure and 62 references (Author abstract modified)