Emergency department (ED) visits for primary healthcare-treatable conditions are preventable and indicate barriers to primary healthcare. The goal of this thesis was to explore the prevalence and key correlates of preventable ED visits among adults in Canada. Our systematic review found that the prevalence of these visits ranged from 4.3% to 59.1% and were associated with younger age, low education, low income, rural residence, and worse self-rated health. Our analysis of data from the 2015-2016 Canadian Community Health Survey found that 39.9% of adults with a regular healthcare provider considered their last ED visit to be preventable. In addition to age, education, and income, these visits were associated with being female, being employed, non-white ethnicity, having no recent consultations with a medical doctor, a strong sense of community belonging, and worse self-rated mental health. Future research should explore the healthcare experiences of these sub-populations to improve their access to care