This volume of Who Was Who contains autobiographical entries for people in Who's Who who died between 2011 and 2015, including biographies for Margaret Thatcher, Lauren Bacall, and Peter O'Toole. Each entry is finally revised and the date of death added. The details in each entry were obtained originally from the individual concerned, and revised by them each year, making this a unique historical resource. There are over 100,000 biographies available over all the volumes of Who Was Who.