Body condition scoring of sheep was first developed as a technique in the 1960s. Unlike live weight, it circumvents the issues of skeletal size, breed and physiological state and is not influenced by gut fill or the length and wetness of the fleece. This review outlines the use of the technique and the relationships between body condition score and other physical measures. In addition, it summarises the literature, across a range of breeds and environments, on the effects of body condition score on reproductive and lactational performance, and the growth and survival of the offspring to weaning. We have proposed that while the relationship between body condition and production traits is positive, it is unlikely to be linear. Where appropriate, the review outlines areas that would benefit from further research. Finally, it outlines what a suitable body condition score profile might be for a ewe over the entire breeding cycle. © 2014 The Royal Society of New Zealand.