What Are Some Needs/shortfalls in Drug Addiction Rehab or Supervised Injection Sites?

this is for a school project and our group wants to perhaps raise money for what is really lacking in the centres that assist drug addicts
but we dont even know what is most needed, and i cant find any site that really tells yuu this
were not sure if were going to fundraise, and if we do would the money be for rehab or injection sites or whatever helps drug addiction
but we could really use the info first, and i might just personally go to one myself to see
thanks!