The transcription factors GATA-4, -5 and -6 are expressed very early in heart tissue. Essential GATA sites have been detected in several cardiac genes and the cardiac GATA factors interact with a wide variety of cofactors which synergistically increase gene expression. These multi-protein transcriptional complexes confer promoter-specificity on the GATA factors and also on the more broadly expressed cofactors. Here we summarise the data on these interactions and represent the conclusions as a GATA factor-based genetic regulatory network for the heart. Of the three cardiac GATAs, GATA-4 is by far the most extensively studied, however, loss-of-function data question its presumed dominance during heart development as opposed to hypertrophy.