“…Moreover, the average working week shows virtually no sign of increasing (Portegijs and Keuzenkamp 2008). Various causes have been proposed for the glass ceiling effect: overt sex discrimination (Bagilhole 1993;Steinpreis et al 1999), the traditional division of household tasks and child care responsibilities (Pittman et al 1999;Wilkie et al 1998), incompatibility of family and professional roles (Probert 2005), sex differences in lifestyle preferences (Hakim 2006), self selection (Van Anders 2004), lower self esteem of women (Kling et al 1999), less support from family, supervisor and colleagues (Van Daalen et al 2005), sex stereotyping (Heilman 2001;Hopkins et al 2002;Willemsen and van Vianen 2008), sexism (Krefting 2003), neglecting sex differences (Pinker 2008) and bias in recruitment and selection procedures (Steinpreis et al 1999;Husu 2001; Van den Brink et al 2006). Although many of the barriers mentioned above have probably been met by women professors, the fact that they actually broke through the glass ceiling may mean that they have found ways to handle them or neglect them.…”