It is strongly advised that a trained interventionist manage the intervention. Family members and loved ones have profound, long-term emotional bonds with the addict. Without the objective perspective and communication skills of a trained professional the addict can often take control of the situation. They can then easily manipulate the emotions of their loved ones, which defeats the purpose of the intervention.
While close family members are normally encouraged to be present, the intervention may also involve co-workers, church members, and any others who care about the person struggling with addiction.