Hi Simon, We got two kittens from Celia Hammond in January so have just been through all this! How long has she been inside for? We kept ours inside for two months as they need to learn the smells and environment of their new home before they go any where else. I agree with what the post above says, let her out when she's hungry and try and get her into a routine so she knows what time of day she goes out. Then when you want her to come in, tap her bowl, call her and give her food and maybe a treat as soon as she comes in so she associates coming back home with something nice. We did this first thing in the morning and in the evening before dark. I would also leave the door wide open the first few times so she know she can run back in for safety if she needs too. Another thing I read is to put butter on their paws when they go out so they sit outside and lick it off while taking in the scent of their new home. Ours have been going out for two weeks now and I was nervous at first but they soon learn when they come in they get cuddles and food etc so do come back! Good luck!