Depending on the number of horses kept together, individual and group housing systems have been developed. Each of these systems has a specific effect on the extent to which horses can satisfy ethologically important traits. Consequently these systems have different impact on the horse welfare, particularly, on their health and the possibility to perform behavioural abnormalities. The purpose of the BSc thesis is to critically evaluate individual and group housing of horses considering their welfare. We used the concept of five animal rights and the AWIN assessment protocol to do this evaluation. Keeping horses in groups, best refines their physical and behavioural needs, in particular the need for social contact, so the lack of social contacts may be one of the key stressors present in individual horse breeding. The smaller area to which individually housed horses are limited may make it also difficult to meet the needs for sufficient movement. In a group of two or more horses, a social hierarchy is present, which is necessary for improved cohesion within the herd. Due to the frequent space constraints, subordinate horses are often unable to withdraw properly to a safe distance and such a situation often leads to injuries resulting from the aggressive social interactions with which the hierarchy is established and maintained. In group housing, lower-ranking horses may be disadvantaged by social dominance to fully satisfy their needs for food, water, shelter, or adequate rest. Such situations occur mainly in group systems, where horses have limited feed resources, insufficient water or feeding places, too little shelter or too few places to rest. Due to the lack of social contacts and movement, individual housing can represents a higher risk for the behavioural abnormalities such as cribbing, wind-sucking, weaving and self-mutilation.