Some things here would be:

• Drug policy liberalization?
• http://www.givewell.org/labs/causes/tobacco-control

See also

• Recreational drug use

External links

• Michael Plant’s series of posts on the Effective Altruism Forum about drug policy reform:
  • Introduction and Cause Summary
  • Six Ways DPR Could Do Good And Anticipating The Objections
  • Policy Suggestions, Tractability and Neglectedess
  • Estimating Cost-Effectiveness vs Other Causes; What EA Should Do Next
• Enthea