To investigate how anti-discrimination legislation in the form of the UK Disability Discrimination Act (DDA) affected socioeconomic disparities in the employment rates of people with a limiting long-term illness (LLTI) or disability.National cross-sectional data on employment rates for people with and without an LLTI or disability were obtained from the General Household Survey (GHS) for a 14-year period (1990-2003; 12 surveys). Representative population samples were analysed. The sample size for the GHS over the study period ranged from 19,193 to 24,657 and the average response rate ranged from 72% to 82%.Age-standardised employment rates for individuals with and without an LLTI or disability, analysed by sex and socioeconomic status.Analysis of covariance identified that the DDA had had a negative effect on employment rates for individuals with an LLTI or disability during the study period. This negative effect was found to be differential according to social class ranging from no effect in social classes I and II (-2.86%, 95% CI -8.7% to 2.99%), increasing with social class group, to a highly significant effect in social classes IV and V (-10.7%, 95% CI -6.16% to -15.24%). No differential effect was identified by sex.Anti-discriminatory legislation is not an effective way of overcoming the employment consequences of ill health and disability, nor is it a useful public policy tool in terms of reducing inequalities.