Direct or indirect recording of systemic arterial blood pressure can be carried out in most animal species. Direct measurements are invasive, requiring arterial cannulation, but this is relatively straightforward in most larger species. Cannulation can be carried out either following surgical exposure of a suitable artery or by puncture through the skin using a specially designed catheter system. The femoral artery can be cannulated in this way in dogs, pigs, sheep and larger primates. Percutaneous cannulation of the femoral artery in the cat and rabbit requires considerable technical skill. In rabbits and sheep, the central ear artery can be catheterised easily using an “over-the-needle” catheter.