Developmental psychopathology is the study of behavioral health and adjustment in a developmental context (Masten, 2006). The study indicates when behavior deviates from normality and goes wrong and also aims to provide a clear understanding of developmental disorders and mental health problems in childhood and adolescence by taking into account the differences that exist in developmental stages as concern several countries. For example, children in Norway start school at age 7, in England at age 5, and in Nigeria at age 2. To understand maladaptive behavior, we must have a clear understanding of normal behavior. For example, in the case of a 15-year-old who cries in anguish because she didn't eat the dessert after the meal, the parents should worry about this behavior, unlike her 3-year-old brother who can be sent to his room when he cries because he didn't eat the dessert. dessert after the meal. This essay presents a preliminary framework diagnosis of a typical example of development gone awry based on a case study (Jessica) who suffered from low mood and behavior changes with a clear rationale of how the diagnosis was made by the DSM- 5 along with some challenges present in the diagnosis of children and adolescents with depression. A list of problems was formed using the framework of predisposing, precipitating, maintaining and protective factors taken from (Carr A, 2006) and finally identifying the intervention/treatment modality based on the preliminary diagnosis. PRELIMINARY DIAGNOSIS Presentation of the case study and according to research from the Diagnostic Statistical Manual of Mental Disorders (DSM-5), the diagnosis was considered for Jessica's difficulty. This diagnosis was made with unc... middle of paper... treatment of depression. This research-based study (Department of Health, 2001) summarized evidence-based information to assist decision making for the most appropriate psychological therapies for diverse patients with a focus on mental health disorders which include depression. This article also states that this is the most comprehensive review of psychological treatment since the review by (Roth & Fonagy 1996). CONCLUSION Correct diagnosis has been hindered due to the difficulties presented in diagnosing depression in children and adolescents. However, despite my uncertainty, the difficulties in the case study met the diagnostic criteria of DMDD and MDD of depressive disorder, so a preliminary decision was made. Although not in depth, studies have revealed that cognitive behavioral therapy is highly effective in treatment