the assertion that children with specific language impairment (sli) do not experience delays in the development of a theory of mind (tom) has been made by numerous researchers (eisenmajer & prior, 1991; leslie & frith, 1988; pemer, frith, leslie, & leekam, 1989; peterson & siegal, 1997). such claims are premised solely upon the results of two studies (leslie & frith, 1988; pemer et al., 1989), both of which suffer from design weaknesses. the present study redressed the weaknesses of past research by administering a broad battery of tom tasks to appropriately aged children and a measure of language ability beyond that of simple vocabulary. the study extended past research and examined the role of working memory and siblings on the tom performance of sli children. the relationship between tom ability and language ability as a means to understanding the elevated incidence rate of behavioural disorder in sli children was also explored. forty nine normally developing and 43 sli children ranging in age from 4- to 7-years completed first- and second-order tom tasks, the information subtest from the wechsler intelligence scale, and the linguistic concepts subtest from the clinical evaluation of language fundamentals test. subjects’ parents completed the child behaviour checklist. results clearly indicated a delay in sli children’s acquisition of tom. their performance deficit extended a the nonverbal tom task and suggests that language has a role to play both in the conceptualization and expression of tom understanding. working memory predicted tom performance for sli children but not that of their peers while number of siblings was not correlated with any tom measure. behavioural symptomology as rated by parents clustered around the normative mean and did not differentiate groups. the importance of language ability and processing capacity are discussed in relation to children’s ability to understand other minds.