Thrombocytopenia is platelet count <1.5 x105/µl and is one of the commonest cause of bleeding. Though not a disease, but it is a consequence of many disease processes. It is a common manifestation of a spectrum of diseases, some of which are reversible, like megaloblastic anaemia, to diseases with fatal outcome like acute leukemia & multiple myeloma.The Preventable causes of thrombocytopenia like infections & anaemia are present in high percentage. Hence most of cases of thrombocytopenia have a favorable prognosis. This work, is about the various causes of thrombocytopenia, its presentations, the commonest cause,and knowing how it can lead to dreadful complications. The book also highlights how important it is to detect the cause of thrombocytopenia to avoid unforseen complications and how a fall in platelet count could be alarming, This book would be a great help to not only the students,but also the pathologists,and clinicians who face this common problem of thrombocytopenia quite frequently, helping them in timely management of the cases priority wise, to avoid disastrous effects.