Reptiles include more than 10000 species, including turtles, tortoises, snakes, lizards, and crocodilians. Most snakes and crocodilian reptiles are carnivorous, whereas many tortoises and turtles are herbivorous or omnivorous. Pet reptiles may be housed in an indoor, enclosed, climate‐controlled area, or 'vivarium', although some might be kept in more open outdoor environments. Reptiles are ... [Show full abstract] generally not sociable and many reptiles may suffer when housed in groups. Human company is not a need for reptiles, and there is no convincing evidence that reptiles enjoy human presence or contact. Some diseases are common to many reptile species, including those caused by viruses, bacteria, fungi, protozoa, worms, and mites. The best method of euthanasia is often sedation if necessary, followed by an injection of an overdose of pentobarbitone into a vein or head trauma in some reptiles. Behavioural stereotypies have been recorded in reptiles, although there is limited understanding of their causes and significance.