The electoral system may affect the structure of opportunities for women. As for the electoral system, there is some empirical evidence that women are generally better represented under PR list systems, than for example, in plurality or majority systems in single-member constituencies. Plurality or majority systems in single-member districts, which tend to work against women, however, are quite seldom in Europe. Combined electoral systems, particularly Mixed Member Proportional Systems, appear to be more conducive to women’s parliamentary representation than plurality or majority systems, but less favourable than PR systems which are applied exclusively in multi-member districts in one tier or at different levels. As for the technical elements of PR systems, larger constituencies make ticket-balancing (at least of large parties) more likely, while the effects of different party list and voting forms depends largely on further conditions (see for further details CDL-AD(2009)029).