Throughout OECD countries there are two types of dominant working time arrangements. The first, and most important, is the standard hours contract. This stipulates precise weekly or monthly hours of work and, predominantly, it involves hours that are confined to weekdays. The second is the standard hours contract plus paid overtime. Usually depending on type of work activity, paid-for overtime hours are either mandatory within the terms of an employment contract or voluntarily undertaken by self-selected individual workers. The importance of these standard contracts is illustrated in the case of Britain in figure 8.1 for males and females over the period 1994–2001. Together they account for over 80 per cent of male and 70 per cent of female workers over the period. It should be added that Britain has one of the highest national incidences of paid overtime (see, for example, figure 2.1, p. 13) but the data in figure 8.1 are reasonably indicative of the general picture. As can also be seen in figure 8.1, other main working time contracts account for relatively low percentages of employees, although flexitime arrangements cover 10 per cent of male and about 12 per cent of female workers. In fact, several of these alternatives – the 4½-day week and the 9-day fortnight – are close derivatives of the standard contract. At least in a British context, there has been little recent indication of a movement away from the standard contracts, both with and without overtime.