In this chapter we explore the intersection of marginalization and suicidal behaviors across three key groups: Indigenous Peoples, sexual and gender minorities, as well as refugee and migrant populations. It draws on various theoretical frameworks, such as Joiner's Interpersonal Theory of Suicide, the three-step theory of suicide, and minority stress models, to help explain the heightened vulnerability to suicidal ideation and behaviors that we see within marginalized populations. Focusing on Indigenous Peoples, in this chapter we address the historical, structural, and cultural factors that contribute to elevated suicide rates in this group, emphasizing the role of colonial legacies, limited access to healthcare, and ongoing discrimination. The chapter further investigates sexual and gender minority populations, whose experiences of minority stress, internalized stigma, and societal rejection exacerbate mental health challenges. This in turn leads to increased prevalence of suicidal ideation and suicide attempts. Lastly, the chapter examines refugee and migrant populations, highlighting how pre- and post-migration stressors, such as trauma, displacement, and exclusion from host societies, elevate suicide risk.