The 19th-century French scientist, Claude Bernard, famously wrote that science is a "superb and dazzling hall, but one which may be reached only by passing through a long and ghastly kitchen".2 Osborne, Simon, and Collins (2003), writing more than a century later, comment that "The essential irony of a discipline that offers intellectual liberation from the shackles of received wisdom is that the education it offers is authoritarian, dogmatic and non-reflexive." ( Cross-country differences in science teaching, and their association with students' performance and interest in a science-related career are presented in Chapter 2 ofVolume II.) In a majority of countries and economies, students from advantaged backgrounds are more likely to expect a career in science - even among students who perform similarly in science and who reported similar enjoyment of learning science. Several actions have been suggested to close this gender gap and, more generally, to encourage more young people, especially those from groups that are now under-represented in science-related fields, to participate in further science-related study and work.