Publisher Summary This chapter discusses a variety of disorders associated with congenital thrombocytopenia. Patients with congenital thrombocytopenia may present with mild mucocutaneous bleeding or petechiae and many congenital platelet disorders are associated with unique physical characteristics, specific findings on the peripheral blood smear, or other associated pathologies. Assessment of the mean platelet volume is stated to narrow down the diagnostic possibilities and in case of genetic mutations, DNA sequencing may aid in confirming the diagnosis. The bleeding manifestations of congenital thrombocytopenias are typically mild and supportive hemostatic agents such as DDAVP and anti-fibrinolytic agents can control the bleeding. Platelet transfusion may be necessary in some cases and special considerations for the management of specific congenital thrombocytopenias are discussed in detail. These disorders include thrombocytopenia with small platelets such as Wiskott-Aldrich Syndrome/X-linked thrombocytopenia, thrombocytopenia with normal platelet size such as familial platelet disorder/Acute myeloid leukemia, and thrombocytopenia with absent radii. Thrombocytopenia with large/giant platelets includes the Bernard-Soulier, Mediterranean Macrothrombocytopenia, velocardiofacial (DiGeorge) syndrome.