After training in Scotland 50 years ago, John worked as stockman on several pig farms and managed several more before joining a large agricultural chemists as pig product manager. He was then technical director of a pig feed concentrate firm and also helped run their pig farm, then the largest in Britain. Head-hunted by Britain's second largest feed firm to be their chief pig advisor, after 12 years he set up on his own as an international pig consultant, where over the past 24 years he has been problem solving on pig farms in 23 countries world-wide. Well-known for his writing on pigs across 50 years, he has written over 3,000 articles and papers, all on pigs, winning several international writing awards. His third pig textbook was published in 2007. His speciality is the cost-effectiveness of pig technology and has published a list of new terms to encourage everyone to measure performance in a more meaningful manner - aligned to profit as well as just physical performance. His monthly column "What the Textbooks Don't Tell You…" for Pig Progress is now in its 15th year.