Type 2 diabetes mellitus (a disease normally appears in the post 40 age group people) now seems to emerging in young adults at the level of global epidemic driven by the increasing burden of obesity. Evidence is accumulating to suggest that this young diabetic cohort is an aggressive phenotype which leads to the premature development of complications that not only have impact on the quality of life but also unfavourably influence the long term outcome, raising the possibility of a serious public health challenge in the next few decades. This chapter reviews the current understanding of the phenomenon of T2DM in the young adults and discusses the clinical challenges in managing this high risk group.