The dilemma in the November/December 2009 issue concerned a client who had heard that his dog could donate blood to a canine blood bank (in Practice, November/December 2009, volume 31, page 527). Vanessa Ashall commented that this presented a complex ethical situation, because while the recipient was likely to benefit from the blood transfusion, the donor did not benefit directly. It was usual to view blood donation from a utilitarian standpoint, in which the aim is to achieve the greatest good for the greatest number and cause the least harm. Maximising benefit to the recipient and minimising cost to the donor were the principles underlying the blood banking system. Costs to donors would usually be related to any stress caused by handling and restraint, so donors with the right temperament should be selected. A possible way forward would be to ensure that the owner was aware Of the criteria used to assess donors and help him assess his dog as necessary. Practice staff would often be more aware of an animal's behaviour in a clinical setting than its owner, and the dog's clinical history should be reviewed and any relevant findings discussed so that an informed decision could be made. The vet had the responsibility of protecting the interests of the donor through careful monitoring of its health and behaviour, and it was important for owner to understand that, ultimately, a vet would decide whether their dog was suitable to donate.