Although most cat owners believe that cats have a need to roam Outdoors and that this activity benefits their welfare, roaming also carries welfare risks for the cat. On the other hand, most cats have not been selectively bred to be "house cats" that live indoors 24 hours a day. Until recently, most domestic cats were allowed to roam freely, and they contributed to the large population of stray and feral cats. In turn many pet, cats come from the stray and shelter population. A large proportion of domestic cats have not been selected for easy adaptation to live in confinement and in close contact with people, and socialization to people may also not have been complete in these cats. However, cats are adaptable to a wide range of environments and are generally not known to show clear behavioral signs of problems, such as stereotypic behavior. Problem behaviors of cats are often not abnormal behaviors per se but natural behaviors that need to be redirected to appropriate substrate,;. The most frequent behavior problems cited by cat owners are: inappropriate elimination, scratching, aggression, anxiety, eating problems, vocalizations, and excessive activity. Despite the frequent reporting of these behaviors, most cats will generally adapt to indoor housing provided there is sufficient space and that they are accustomed to these conditions from an early age. The Five Freedoms, developed to assess the welfare of farm animals in intensive systems, can be modified to assess the welfare of cats housed in confinement. Specific features of the environment that can enhance the. welfare of cats in confinement are discussed. (C) 2007 Elsevier Inc. All rights reserved.