Previous research has suggested that working memory difficulties play an integral role in children's underachievement at school. However, working memory is just one of several executive functions. The extent to which problems in working memory extend to other executive functions is not well understood. In the current study 38 children with a poor working memory, and 38 age-matched controls, were tested on measures of shifting, inhibition, planning, and attention, and were also rated by class teachers on the Working Memory Rating Scale. Scores obtained by the two groups were compared in order to identify whether children with a poor working memory have a generalised executive impairment, or problems specific to working memory. The results revealed that children with a poor working memory achieved significantly lower scores on measures of planning and attention, but not shifting and inhibition. Specific relationships also existed between cognitive and behavioural aspects of working memory, with scores on the Working Memory Rating Scale being significantly associated with working memory, planning, and attention, but not shifting and inhibition. The results are discussed in terms of implications for both theory and practice. (Contains 2 tables.)