Catastrophic antiphospholipid syndrome (CAPS, Asherson's syndrome) is an unusual form of antiphospholipid syndrome (APS) characterized by multi-organ failure and high mortality. Fortunately, CAPS accounts for less than 1% of APS cases. Due to the rarity of the condition, an international registry of CAPS patients was created in 2000 supported by the European Forum on Antiphospholipid Antibodies held in Taormina, Italy at the Tenth International Congress on Antiphospholipid Antibodies. Clinical and laboratory features are the most important in the criteria for the diagnosis of this syndrome and can affect many organ systems. The majority of patients presented with multiple organ involvement at the time of CAPS. The combination of pulmonary, cardiac, and renal involvement was most commonly seen. The organ systems most commonly involved at the onset include the cardiopulmonary system, primarily characterized by dyspnea and respiratory failure, the central nervous system, and the renal system. Laboratory criteria for the classification of CAPS include the presence of antiphospholipid antibodies-LA and/or aCL and/or beta(2)-GPI antibodies.