The 18q deletion syndrome (18q-) is a chromosomal disorder involving deletion of the distal segment of chromosome 18. Typifying features include poor cerebral myelination, reduced intellectual functioning and developmental delay. The present study reports the case of an 8-year-old girl diagnosed with 18q-, whose genetic analysis revealed a break at q21.3. Comprehensive neuropsychological testing indicated impaired functioning across most cognitive domains. However, verbal abilities were intact. Given the preservation of verbal skills on a background of relatively global impairment, CB's genetic and cognitive profile has implications for delineation of neuropsychological features associated with specific breakpoints in 18q-.