There are still persistent conflicts in the policy and legal landscape. The central government has given explicit support to harm reduction, for example, as stated in the Medium-and Long-Term Strategic Plan and the Action Plan. Some programs have been implemented successfully [36,50,51]. However, in China, as in many other countries, public health and public security authorities frequently approach drug abuse from different perspectives, leading to conflicting approaches at local levels. The crackdown philosophy and detention of drug users in China reflect inconsistent interpretations of "harm reduction" and present a challenge to public health officials in implementing methadone substitution and needleexchange programs [52] . Drug users may be reluctant to participate in these programs due to fear of being caught by police officers [50] . It might be impossible to completely solve the dilemma in the near future, but this conflict is expected to gradually reduce for the following reasons. First, Chinese national policies for HIV prevention and control have become much more pragmatic in the past years. MMT and needle exchange programs were almost unimaginable several years ago, but now they are ready to be expanded across the country. We expect that the open policy trend will continue as the Chinese economy is increasingly merged with international markets, and this trend will favor harm reduction programs. Fur-thermore, China's centralized government may achieve an advantage in promoting public health policies if these policies are believed to be correct. Second, inter-agency coordination on public health crisis has been enhanced at both central and local governmental levels since SARS outbreak in 2003, which reduces potential conflict of public health policies. Public health workers should provide policy advocacy to public security authorities and help them change their traditional norms about illicit drug control and obtain their supports for harm reduction. Third, operational research is needed to provide evidence on the benefits of harm reduction programs and convince policy enforcers and lead to revision of unfavorable policy components.