As a result of the evaluations, it has been determined that an added 20.7 million people have a drug use problem. Forty percent of these people also suffered from a second mental illness. Participants came from both developed and underdeveloped countries as part of an international study conducted by the World Health Organization (WHO). According to the findings, there is a consistent pattern of high rates of mental disorders all over the world, although there are some differences in lower rates in Asian countries (Demyttenaere et al., 2013). Similarly, a meta-analysis of twenty-seven studies involving more than 150,000 participants from sixteen different European countries found that approximately 27% of people had been diagnosed with at least one mental disorder in the past 12 months (Wittchen & Jacobi, 2005). The Institute of Medicine and National Research Council meta-analysis of more than fifty studies from community samples from around the world reported a 17% prevalence rate for one or more mental, emotional, or behavioral disorders in youth, and about half reported significant functional impairment (O'Connell, Boat, and Warner, 2009). This study focused on children and adolescents. O'Connell, Boat, and Warner (2009) conducted the study. The results of the Global Burden of Disease study show that, even though we must bear in mind, disability-adjusted life years (DALYs) associated with 'mental and behavioral disorders' increased by approximately 36% between 1990 and 2010. The study was conducted by the World Health Organization (WHO) (Murray et al., 2013). DALYs represent the total number of life years lost due to disability and the years lived with it (Murray and Lopez, 1997). In conclusion, the evidence accumulating throughout the substantial number of studies conducted in various nations shows that mental disorders are common and there are emerging numbers of individuals who meet the diagnostic criteria for a mental disorder.