An examination of gender, social class and ethnicity performance and participation patterns in different UK countries shows that inequities occur in relation to gender, class and ethnicity but that the patterns of inequity look quite different in the three domains. Achievement is equal for different genders but many more males take mathematics forward to advanced levels; social class differences persist in both achievement and participation; and ethnicity shows a varied pattern with some groups performing and participating at particularly high levels and some particularly low. This paper identifies some critical issues that we face in making mathematics and science equitable and begins to analyse some of the barriers that stand in the way of students who are female, and from some ethnic and social groups. (Contains 1 note, 7 figures and 7 tables.)