Friend of GATA‐1 (FOG‐1) is a zinc finger protein that has been shown to interact physically with the erythroid DNA‐binding protein GATA‐1 and modulate its transcriptional activity. Recently, two new members of the FOG family have been identified: a mammalian protein, FOG‐2, that also associates with GATA‐1 and other mammalian GATA factors; and U‐shaped, a Drosophila protein that interacts with the Drosophila GATA protein Pannier. FOG proteins contain multiple zinc fingers and it has been shown previously that the sixth finger of FOG‐1 interacts specifically with the N‐finger but not the C‐finger of GATA‐1. Here we show that fingers 1, 5 and 9 of FOG‐1 also interact with the N‐finger of GATA‐1 and that FOG‐2 and U‐shaped also contain multiple GATA‐interacting fingers. We define the key contact residues and show that these residues are highly conserved in GATA‐interacting fingers. We examine the effect of selectively mutating the four interacting fingers of FOG‐1 and show that each contributes to FOG‐1's ability to modulate GATA‐1 activity. Finally, we show that FOG‐1 can repress GATA‐1‐mediated activation and present evidence that this ability involves the recently described CtBP co‐repressor proteins that recognize all known FOG proteins.