The phenotypic heterogeneity of the velocardiofacial syndrome (VCFS) or Shprintzen syndrome caused by a chromosomal 22q11 deletion will be discussed. The acronym 'CATCH22' (Cardiac defects Abnormal facies Thymic hypoplasia Cleft palate Hypocalcaemia) has been suggested to indicate the associated phenotype. The variable clinical phenotype was previously recognized as DiGeorge syndrome and Shprintzen syndrome, but both are caused by a microdeletion of chromosome 22q11. However, most patients show only partial expression with mild clinical features. Through a sensitive genetic investigation called FISH (Fluorescence in situ hybridization) a diagnostic test of VCFS has become routinely possible, leading to an increased number of patients that are diagnosed. Early diagnosis is very important to recognize associated problems, to initiate adequate treatment and to provide necessary genetic counselling.