Henoch-Schönlein purpura (HSP) is a small-vessel vasculitis primarily affecting children, characterised by the tetrad of palpable purpura, often on the buttocks and legs, abdominal pain, arthralgia, and renal involvement. It matters in clinical practice due to its potential complications, including nephritis, which can lead to chronic kidney disease. HSP is often associated with preceding upper respiratory infections, highlighting the need for careful monitoring and management.