On behalf of CPSG, I extend our condolences to Mark's family. Every remembrance I have read has mentioned Mark's smile, and rightly so. No one who met him will forget it or the charming and mischievous laugh that often accompanied it. We can only imagine the hole his passing leaves in the family but hope that the scores of people around the world remembering him and missing him with you will help to fill it, if only just a little.