Common variable immune deficiency is a primary immune deficiency disorder characterized by reduced serum immunoglobulins and heterogenous clinical features. The clinical features of CVID amongst adult populations have been well described however there are few studies specifically describing the demographic and clinical features of CVID in childhood. This is a retrospective chart study that reviews the clinical features of 16 children diagnosed and treated with CVID at the Royal Children’s Hospital in Melbourne from January 1993 until August 2005.  We compare our findings with those previously published for adult CVID populations and note potential differences in sex distribution, clinical manifestations and immune function investigations. Specific features of childhood CVID not previously reported for adult CVID include: a higher incidence in males (70%) and a greater frequency of cytopenias, especially thrombocytopenia (38% in childhood vs 11-22% in adults). A possible association with midline defects in children was also identified. .Our findings also suggest that CVID should be considered not only in children with recurrent infection, but also in children presenting with growth failure or cytopenias. Additionally, we found that paediatric patients with CVID have a significantly lower incidence of impaired T cell function and absence/impaired antibody response to polysaccharide antigen is a more sensitive marker of impaired antibody production than protein antigens in children with CVID.