Intimate partner violence (IPV) is defined by the World Health Organization as any behaviour within an intimate relationship that causes physical, sexual or psychological harm. Much of the extant research focuses on female survivors of IPV, with much less focusing on male survivors of IPV. The overarching goal of this thesis was to better understand the measurement, prevalence, risk factors, and psychosocial consequences of IPV for both men and women. This thesis utilises two nationally representative samples of adults from the Republic of Ireland and Ontario, Canada. After an extensive assessment of the psychometric properties of a self-report measure of IPV, it was found that approximately one-in-three women and one-in-four men in Ireland, and one-in-three women and one-in-six men in Ontario, experienced IPV within their lifetime, with women having more varied and diverse IPV experiences than men. Risk-factors for IPV were identified for males (e.g., having children & low social support) and females (e.g., having children & lower income), and IPV experiences were shown to be positively associated with multiple negative mental health variables (e.g., suicidal ideation, internalizing distress). Findings indicate that loneliness, but not social contact, partially mediated the association between IPV and internalizing distress. The factors involved in male and female victims’ decisions to stay with or leave their abuser were investigated, with results finding that feelings of guilt, shame, or embarrassment, and having a safe place to go were the most cited reasons for staying or leaving, respectively. Finally, it was shown that symptoms of depression could be measured equivalently for those with and without a history of IPV. This thesis provides methodologically rigorous data about the valid and reliable measurement of IPV, its prevalence in the population, associated risk factors, and gender specific details about why people remain with or leave abusive partners.