Intervention does not have to be a formal confrontation of the afflicted person by a group of people. It can be any number of triggers that add up to move a person along a continuum toward help-seeking and wellness. A conversation can be a powerful tool.

1. Parents should first talk privately with each other to get on the same page about how they are going to address their child. You should answer screener questions to find out the extent of the problem.
2. You should find a time to hold a conversation with your child when he or she is not high or drunk, and when they are not extremely upset or angry.
3. You should initially express love and concern for your child's safety and well-being as the basis for the concern, whether the child acknowledges this or not.
4. You should point out that, while it is the child's responsibility to grow up, it is your job as parents to make sure he or she reaches adulthood as safely as possible.
5. You should tell your child the warning signs you've observed in his or her behavior that have made you concerned, and use the findings of the screener to say that this problem warrants serious attention and family support, as well as professional help, because it can get out of control and can even be fatal. This may include negative effects of the person's substance use on you, and on those surrounding. However, it is extremely important to remain neutral and non-judgmental in tone, like a news reporter. To sum up the warning signs at this step, you should state that the pursuit of substance use despite adverse effects on yourself or others is actually the definition of "drug addiction." Don't press the child to agree on this assessment of the problem.
6. You should then listen to anything and everything the child has to say in response. If he or she brings up related problems, they should be listened to with a promise of being addressed separately. But you should reiterate that what you are addressing at the moment is substance abuse, which is serious and can be at the core of other problems.
7. Then you should follow the practice of "motivational interviewing" used by clinicians, to empower your child and get them to think about their substance use in a new way. Ask questions about what the child wants his or her life to be like at this stage — school, relationships with friends, relationships with parents, siblings, job, activities, etc. Ask how things are going in each of these areas, and listen. You are holding up a mirror on their life and letting them look at it fresh.
8. The listening step is crucial, to establish empathy and to convey that you really see and hear your child, and are taking them in. Prompt your child to consider the link between substance use and where their life is not matching up to his or her dreams and wishes. Our kids are generally not self-destructive; they want to do what serves them in their lives. They don't want to be patronized, and do want to be trusted with your expectation and full confidence that they can, and will, do the best thing for their own health and their family.
9. Ask the child -- in light of what he or she is concluding in this conversation about the substance abuse effect on his or her life -- to reassess the problem. Set a goal for getting well. Plan together some concrete next steps to find information about addiction, recovery and resources, and identify professional help that will be most suitable.
10. You and your child should understand that the conversation you just had is actually a successful "intervention," a first concrete step toward interrupting the progression of the problem and getting well. It is a good idea to reiterate again your love and caring concern for your child. Acknowledge yourselves, knowing that you need and deserve strong encouragement and support, and have the power to solve this problem together.