The nature and prevalence of preschool children's language delays in an economically disadvantaged Brisbane community was investigated using three standardised language measures. The instruments assessed children's expressive vocabulary knowledge, receptive vocabulary knowledge, and provided measures of language form and grammar. These aspects of language were investigated in a sample of 157 children exiting preschool (mean age 5 years 3 months). Nineteen percent of the children performed at, or below, the 4-year-old level on the expressive vocabulary test and thirty-eight percent of the children had receptive vocabulary scores below the 4-year-old level. Grammar and language form were also significantly delayed. The educational implications of these delays are discussed along with suggestions for interventions. The research is part of a joint project conducted by Griffith University, Mission Australia and Education Queensland and funded by the Australian Research Council.