The Monitor provides epidemiological trends in alcohol, tobacco and other drug use; problem use; public opinion regarding drug issues and policies; and mental health among Ontarians. About 3,000 Ontario adults are interviewed each year using various modes. The report provides the latest estimates of substance use and related harms, and mental health and well-being indicators among Ontario adults. The CAMH Monitor survey spans 47 years, and the 2023 report examines the changes in estimates between 2022 and 2023 surveys. It also compares estimates of substance use and mental health indicators from 2023 to those from five years (2018) and ten years (2013) ago.