Intervening variables are factors that have been identified as being strongly related to, and influential in, the occurrence and magnitude of substance use problems and consequences. Risk and protective factors are types of intervening variables. Risk factors are individual characteristics and environmental influences associated with an increased vulnerability to the initiation, continuation, or escalation of substance use.

Protective factors include individual resilience and other circumstances that are associated with a reduction in the likelihood of substance use (Hawkins & Catalano, 1992).

For each intervening variable listed below, there are a set of local conditions. Local conditions describe why something is or is not a problem--this is how the intervening variable manifests itself at the local level. For example, social access/availability is an intervening variable while a related local condition might be alcohol availability at community celebrations. Local conditions can be monitored and measured using specific indicators. For the example provided, one specific indicator might be lack of wrist bands for persons under age 21 at community events where alcohol is sold.