I would not leave my 14 yr. old Cocker Spaniel more than 3-4 hours alone. Since Carly is a senior citizen, she has to potty every 4 hours, day and night, which I supervise and although she sleeps a good part of the day, she still has to be watched during her waking hours. However, when Carly was younger, I worked and was away from home 9-10 hours 5 days a week. I had a walker who would take her out to potty and walk her and her food and fresh water was always available. I would give her a short walk in the early morning and potty and when I arrived home, another short walk and potty. Everything worked well but Carly is older now and has a few health conditions which require medication. So it all depends on age, health and habits. Again, I would not think of leaving Carly more 3-4 hours unless she was cared for by a sitter. My life now revolves around Carly so if I have to travel, I would find a stay-at-home sitter and confirm if he/she was able to care for her under these conditions.