Within any flock of sheep there is a substantial variation in the characteristics that influence an animal’s production level. Using EID or RFID tags to identify each sheep allows farmers to understand these variations which provides opportunities to select or sort animals based on different criteria such as scanning results, breed, growth rate and so on to make informed management decisions for the operation. Electronic ID allows farmers to measure the performance of individual animals and make decisions specific to each animal, reducing costs and labour, while at the same time maximising returns.