Multiple and overlapping disadvantages that are often persistent and interrelated and affect a person's life. These disadvantages include the experience of homelessness, harmful drug or alcohol use, criminal justice involvement, poor mental health, and the experience of domestic violence and abuse. People experiencing severe and multiple disadvantage have often experienced underlying adverse childhood experiences, poverty, psychological trauma, stigma and discrimination. People with these experiences may have had sporadic and inconsistent contact with services or been serially excluded from services. People who experience severe and multiple disadvantage tend to have much poorer physical and mental health, have higher social care needs, and die at a much younger age than people without severe and multiple disadvantage.