There are three critical phases to an eating disorder intervention: the planning, the intervention and the follow-up. Both the eating disorder and the intervention are highly emotional issues, so it is recommended that families include a professional in the process. Also make sure you focus on the main goals of the intervention throughout each phase. The first goal is to get your family member with the eating disorder to seek appropriate treatment. The second goal is to get your family out of a crisis situation that so often happens when a family member has such a problem.
As you plan the intervention, you need to decide who should be involved. Children shouldn't be involved; you can have the child write a letter or draw a picture of his/her feelings to be shared at the intervention, but without being present. There may be friends who should attend the intervention as well. However, since many people suffering with eating disorders can be in denial or defensive, you don't want to include everyone who might want to attend. As you plan with the attendees, decide what it is you want from the sufferer (e.g., go to residential treatment, see a therapist, etc.) and put logistical plans in place to help him/her take that action. The attendees also want to decide what the consequences will be if the sufferer doesn't take e action. The consequences can be different for different attendees, but everyone should know what his/her personal plan is.
It's not advised to tell the sufferer about the intervention before it happens. Once it begins, make sure it progresses in a supporting, loving manner. Attendees usually read prepared letters detailing how the sufferer's illness has impacted them and their fears for the sufferer. They will also discuss specific examples of worrisome behaviors and their impact. Eventually, attendees will share their request for change with the sufferer and explain the consequences of not complying. Then, it is critical for the attendees to follow-up, either with support for the treatment taken or with the consequences.