This document summarizes substance and drug abuse. It defines substance abuse and different types of drugs abused like depressants, hallucinogens, stimulants and opiates. It mentions that 35 million people worldwide suffer from drug use disorders and only 1 in 7 people receive treatment. It outlines the current situation, burden, signs and symptoms, causes from a familial and childhood perspective. It discusses a public health approach to define the problem, identify risk factors, develop and test interventions, and monitor impact. Key strategic priorities are outlined like reducing stigma and changing social norms. Treatment approaches discussed include behavioral counseling, medication, treatment for co-occurring issues, and long-term follow-up.