Indoor cats live longer and safer lives than outdoor cats in many environments, but confinement without adequate enrichment causes chronic stress, boredom, and behavioural problems that represent serious welfare concerns.
Indoor confinement protects cats from road traffic, predation, disease, and injury, but creates a welfare obligation to provide the environmental complexity that outdoor access would otherwise supply. Cats deprived of hunting outlets, vertical space, hiding places, and social or cognitive stimulation develop chronic stress expressed as overgrooming, house soiling, aggression, or lethargy. Welfare science for indoor cats has advanced significantly, producing evidence-based enrichment protocols that transform a barren apartment into an environment that meets feline behavioural needs. Enrichment is not a luxury but a welfare necessity for indoor cats.