The welfare of seven domestic cats housed singly in a quarantine cattery was studied for six months. Behavioural data were obtained with cameras and by time-lapse video recording, and cortisol to creatinine ratios were measured in urine samples collected from litter trays. It took five weeks for the cats to show evidence of adaptation to their new environment. They spent most of the first two weeks concealed in a house on the floor of their cage. As they adapted, they spent less time hiding and more time higher in the cage. The cats were inactive for approximately 90 per cent of the time observed, and they received little human contact. Compared with the first day, the cats' cortisol to creatinine ratios were significantly lower from their second month in quarantine.