Martin E. Hellman is a remarkable man.  He is perhaps best known for his invention, with Diffie and Merkle, of public key cryptography- the technology which (amongst other uses) enables secure internet transactions and is used to transfer trillions of dollars each day.   His work has been recognised by numerous honours including his election to the National Academy of Engineering, the National Inventors Hall of Fame and most recently- receiving the 2015 ACM Turing Award, the most prestigious honour In computer science. In this exclusive interview, I spoke to Professor Hellman on how, as our capabilities accelerate, our society must approach the ethics of technology.