The Sex Discrimination Act makes it unlawful to discriminate in employment on the ground of sex or marital status. So, a job advert for a 'salesgirl', or an advert which says 'must be nimble fingered, to work in a predominately female environment' which implies packing jobs are restricted to women, are likely to be unlawful. The Sex Discrimination Act also makes it unlawful to discriminate on the ground of sex in relation to education and training, the provision of goods, facilities and services or the disposal of premises.
To find out more about employers’ obligations when placing job advertisements, read Employers: job advertisements and equality.
For more about discrimination in recruitment and selection, see Rights in action: working and earning.