The solution to fine tuning is one of the principal motivations for beyond the standard model (BSM) studies. However constraints on new physics indicate that many of these BSM models are also fine-tuned (although to a much lesser extent). To compare these BSM models it is essential that we have a reliable, quantitative measure of tuning. We review the measures of tuning used in the literature and propose an alternative measure. We apply this measure to several toy models and the minimal supersymmetric standard model.