The four main aims of this cohort study were to (1) determine the number of consecutively referred low birth weight (LBW) infants presenting with delayed language at 12 and 24 months of age, (2) examine language profiles by measuring both functional and spontaneous language ability in 24-month-olds, (3) examine the relationship between perinatal medical history and language status at 12 and 24 months, and (4) examine the clinical validity of the Early Language Milestone (ELM) scale, a brief language screening instrument. Only infants without serious sensory impairment or mental handicap were included in the final sample. Seventy-one LBW infants (36 12-month-olds, 35 24-month-olds) were seen for developmental and language assessments. The findings suggest that within the first 2 years of life, low to moderate rates of language delay are evident in LBW infants who have already been screened for serious sensory or mental handicap. At 12 months of age, 8.3% of the infants had delayed expressive language; none had delayed receptive language. At 24 months of age, 28% of the infants had delayed expressive language; 5.7% had delayed receptive language. Furthermore, only 32% of those with normal expressive language and sufficient language sample had a mean length of responsewithinthe normal range. Language status was not related to a specific perinatal medical variable. Additional study into the clinical validity of the ELM as a screening measure for the LBW population is warranted. The ELM specificity for both receptive and expressive language domains was good at both ages (80 to 100%), but sensitivity was low to moderate (0 to 68%).J Dev Behav Pediatr 14:21–27, 1993.Index terms:language development, low birth weight.