My partner is bringing a 3-year-old German shepherd guard dog from work, into the family home. How will it fit into the home environment?

To a large extent, this depends on the individual dog, how sociable he is, and whether he is used to living in a kennel or indoors. If the dog is good-natured but trained to guard, then its important you feel confident giving him commands and expecting obedience so that he doesn't act up. This could mean going to dog training classes with him in order to learn how to take control. Bear in mind that a dog reared and kept outdoors may not be suitable for a family home, so have an honest talk with the trainer about your concerns, and never put children at risk.