An Adverse Childhood Experience (ACE) refers to a potentially traumatic incident that occurs in childhood, specifically between the ages of zero to 17. The term comes from a study published in 1988 and consisted of a ten-item questionnaire listing “adversities” that may have taken place in the first 18 years of life. Respondents would receive a score between zero and 10 depending on whether they had or had not experienced the listed “adversities.” The items covered 10 types of adversities, including witnessing or receiving verbal, physical, sexual, and domestic abuse; neglect; poverty; parental separation; and witnessing substance use disorder, mental illness, or incarceration on the part of the caregivers. Gaps or misrepresentations of the study include the limited cultural and socioeconomic representation of its respondents, who were mostly white, middle-class individuals; the failure to identify the age at which an ACE took place and the existence of any buffering factors; and the tendency to confuse correlation of ACE score and adult health conditions with causality. An ACE is differentiated from trauma in that an ACE specifically refers to an event taking place in childhood, and with reference to the study, only refers to 10 potential adversities. Trauma more broadly can result from other kinds of adverse incidents that occur later in one’s life as well.