Major depressive disorder (MDD) is the most common mental disorder. It can be a huge burden not only for the person affected by it, but also for his/her whole family. The goal of this clinical trial is to test the efficacy of a family supportive intervention called psychoeducational family intervention (PFI) compared to a brief informative intervention in families with a member affected by MDD. Families will participate in one of the two interventions for a period of 6 months more or less, and they will be asked to answer some questionnaires about how much MDD impacts on their everyday life and the patient's symptoms, in order to understand whether a more structured intervention such as PFI can be useful for families in order to better deal with this complicated illness.