Due to the peculiar anatomy and characteristics of the skin of reptiles, historically intravenous catheter placement in reptiles has been considered challenging. However, intravenous catheter placement is as essential in reptiles as in every other species. Intravenous catheters are currently used in reptiles to promptly rehydrate critically ill reptiles, provide blood transfusions, titrate more precisely drugs during general anesthesia, and administer contrast during advanced diagnostics, such as computed tomography and magnetic resonance imaging. In this masterclass, I will share some of the information that I found useful in order to place IV catheters in reptiles. Depending on the size and the species of the reptile, different techniques are more indicated for IV catheter placement. We will cover placement of catheters in the jugular vein, ventral and lateral tail vein, cephalic vein, ventral abdominal vein, among other vascular site, in chelonians, snakes and lizards.