Immune thrombocytopaenia (ITP) is the most common cause of acquired thrombocytopaenia diagnosed in paediatric patients. It is described as an isolated thrombocytopaenia without other factors, which may cause a decrease in platelets. Therefore, the diagnosis is of exclusion. Over the last few years, its management has significantly developed, and a paradigm switch in second-line treatment is being observed. Currently, thrombopoietin receptor agonists (TPO-RA) are available in Poland, which reduce the need for splenectomy in affected patients. The use of thrombopoietin receptor agonists has also provoked a change in definitions, especially concerning refractory ITP. This review focuses on an overview of currently recommended diagnostics and treatment of ITP, ongoing research concerning genetic predisposition, the use of TPO-RA, other immunosuppressive agents, and the role of splenectomy. We summarise congenital thrombocytopaenic disorders, which are the most often mistaken as ITP and need to be considered in the differential diagnosis.