Interesting thread topic, and one I've often thought of asking myself. With clicker training in the house, it doesn't matter what the reward treat is, Chloe just goes mad for the "click" and even a bit of bread or a hug does it for her! Outside, its a different matter; I use different things for recall training - livercake, hot-dog sausages, and roast chicken are her faves, but I can't always guarantee that either one of them will work, it seems to depend on her mood