Abstract: Many aspects of horse care and handling are based upon convenience and traditional practices. Many of these methods of management and practice do not take into account the natural behaviour of horses. This is despite the belief that although domestic horses are probably more docile, stronger, faster growing and faster moving than their ancestors, they are unlikely to have lost any natural behaviours. The performance or sport horse is expected to perform a wide variety of movements and tasks, some of which are unnatural or exaggerated and most of which must be learned. The term “training” is commonly used to describe the processes whereby the human handler introduces the horse to new situations and associations. Performance horses are often required to tolerate stimuli that are innately aversive or threatening, such as having a person on their backs. They are also trained to respond to a stimulus with often unnatural or over-emphasised behaviour, such as some of the dressage movements. Effective and humane training requires an understanding of the processes underlying behaviour. These include knowledge of behaviour under natural conditions, learning processes, the influence of early experience and motivational forces. Horses differ from the other main companion animal species, namely cats and dogs, in that they are a prey species. They most commonly flee from dangerous and painful situations. Horses readily learn to avoid potentially threatening situations and if their attempts to avoid associated stimuli are prevented, they will often exhibit problem behaviours. In this chapter the history of horse training, the application of learning theory and a knowledge of equine behaviour to training, and innovative training methods are all considered.