Description: In all 35 countries which participated in PIRLS 2001 there were differences in reading performance between boys and girls. Girls outperformed boys from 8 to 27 points (20 on average), with exception of one country where the difference was 48. When we look from the point of a single country it seems that something must be done to reduce the difference, however, when we look at all countries at the same time there are only minor differences: where girls are top performers, boys are top performers as well - and vice versa. This leads for us to the conclusion that if we want boys to become better readers, everything we do for girls would move boys on the scale of reading score higher as well.With multivariate analyses we will try to establish which factors influence the differences between boys' and girls' performance. We will take a closer look on two countries: Sweden and Slovenia because they both tested 3rd grades (Sweden also tested 4th grade which was the best performing population in the survey), the students were exactly the same age and the differences between boys and girls was almost the same (22 vs. 21 points).