Fungi are a rich sources of secondary metabolites that are relevant to human health, including antibiotics and fungal toxins. However, our understanding of the regulation of secondary metabolite biosynthetic gene clusters is limited. Oakley et al. carried out a genetic screen in Aspergillus nidulans and discovered a previously uncharacterized gene that is predicted to encode a zinc-finger transcription factor. This transcription factor was shown to function as a negative regulator of important secondary metabolite biosynthetic gene clusters and they thus termed the gene multicluster regulator A (mcrA). Deletion of mcrA led to the identification of two secondary metabolites and the finding that A. nidulans produces the antibiotic, felinone A. Thus, deletion of mcrA homologues in fungi is a promising tool for the discovery of novel compounds.