Dr David Murphy, Visiting Professor in Practice at ÐÓ°ÉÂÛ̳ Law School and an expert in financial regulation, has a long term research project on the variability of margin. The tendency of margin requirements to increase when financial markets are stressed creates significant stress, and has been the focus of regulatory attention for some years since Dr Murphy's In a recent paper with the World Federation of Exchanges' Dr Pedro Gurrola Perez, Dr Murphy unveiled an innovative new approach to measuring the reactiveness of margin. This answers a question posed by regulators Gurrola Perez and Murphy's approach is being implemented by a number of leading global market infrastructures.