This course offers a window into the drivers, patterns, and consequences of substance use among women throughout the lifecourse. Through assessment of current evidence, reflection and discussion, application of multilevel theoretical frameworks, and engagement with practitioners and researchers, we will explore the complexity of sex and gender differences in substance use. We will review current trends in substance use among women, explore specific topics of public health significance (e.g., pregnancy, interpersonal relationships, infectious disease transmission, stigma, and disparities), contrast understandings of substance use acquired through quantitative and qualitative research methods, and critically evaluate prevention, harm reduction, and treatment approaches. This course will provide you with a deeper understanding of the significance and complexity of substance use and related issues among women.