The aim of the current programme of research was to determine if the IRAP, a recently developed methodology for the assessment of implicit cognition, is a useful measure of implicit racial bias in the Irish context. Over the course of a series of experiments, the research refined the IRAP and examined its relationship with various alternative attitudinal indices, including self-report measures and measures of behavioural intentions. In addition, the fifth experiment explored the predictive validity of the IRAP using knowngroups, while Experiment 6 investigated the relationship between neural activity, measured with electroencephalograms, and IRAP responses. In the final experiment, the malleability of IRAP performances, as a result of acceptance and education-based interventions, was investigated. Overall, the research reported in the current thesis provides support for the reliability and validity of the IRAP and suggests that it is a relatively robust measure that could be used in subsequent research in the study of implicit racial bias.