The etiology of Kawasaki disease (KD) remains unknown despite several years of dedicated research in this direction. Recently coronavirus infection and genetic polymorphisms have been implicated. Since first description of the disease there have been few changes in the diagnostic criteria except for newer recommendations of fever of at least 4 instead of 5 days duration. Recently, Echocardiography Criteria and Laboratory Criteria have been added to aid in the diagnosis of incomplete KD where all the historical diagnostic criteria are not present; this is now called the "incomplete form of KD" as opposed to "atypical form of KD". The word "atypical" is reserved for unusual presentations of KD such as those with hemophagocytic syndrome or nerve palsy. The treatment of KD includes infusion of high dose immunoglobulin. Patients non-responsive to immunoglobulin therapy are labeled as having "immunoglobulin resistant KD". The treatment of immunoglobulin resistant KD can be challenging and new therapies that have tried with some success. Late outcomes after 4 decades of treating these patients have recently been published. There has been some concern about increased risk for premature atherosclerosis in patients with childhood KD who had coronary artery abnormalities.