The largest proportion of the world's horses are still used for work in agriculture and traction, however in the western countries they are increasingly kept for recreational and social purposes, breeding, sport and competition. It is often assumed that horses enjoys better farming conditions than other species, yet they have specific needs which should be fulfilled in order to have a proper welfare. This paper will review the main welfare issues of horses and the following aspects will be considered: nutrition, housing and management, clinical problems, behaviour problems, training and riding, transportation, measuring welfare. Horses are social animals that live in groups in close contact with conspecifics. They spend most of their waking hours moving at walk, grazing and eating grass. Some of the constraints imposed on horses during the last centuries conflict to their naturally evolved behaviour. Effective and humane handling of horses positively affects many important aspects like the safety of man, the performance level and the welfare of horses. It is an essential condition for keeping horses that handlers, riders, trainers, farriers and veterinarians have proper knowledge of the behaviour of the horse in order to fulfil their natural needs and guarantee their welfare.