Platelet-related bleeding is an alteration of primary haemostasis dependent on a reduction in the number and/or function of blood platelets. Affected patients display predominantly mucocutaneous symptoms of variable severity. The risk of bleeding is greater in patients with platelet counts below 50,000/μL and/or severe dysfunction, for instance, due to Glanzmann thrombasthenia or Bernard-Soulier syndrome. The assessment of patients with possible platelet-related bleeding should include careful collection of the personal history using a validated bleeding assessment tool (BAT) and documentation of possible bleeding signs by physical examination. Concomitant factors such as anaemia, haemocoagulative abnormalities, fever, and comorbidities may differently modulate a haemorrhagic phenotype of platelet origin.