This review explores the emerging evidence regarding pathogenesis, future trajectories, treatment options, and phenotypes of youth-onset type 2 diabetes (T2D).Youth-onset T2D is increasing in incidence and prevalence worldwide, disproportionately affecting First Nations communities, socioeconomically disadvantaged youth, and people of colour. Youth-onset T2D differs in pathogenesis to later-onset T2D and progresses more rapidly. It is associated with more complications, and these occur earlier. While there are limited licensed treatment options available, the available medications also appear to have a poorer response in youth with T2D. Multiple interacting factors likely contribute to this rising prevalence, as well as the increased severity of the condition, including structural inequities, increasing obesity and sedentary lifestyles, and intergenerational transmission from in-utero exposure to maternal hyperglycemia and obesity. Youth-onset T2D is also associated with stigma and poorer mental health, and these impact clinical management. There is an urgent need to develop effective interventions to prevent youth-onset T2D and enhance engagement of affected youth. It is also critical to better understand the differing phenotypes of youth-onset T2D, to effectively target treatments, and to address intergenerational transmission in high-risk populations.