Genes that control cell fate in all major root tissues have been described in Arabidopsis and new candidates that pattern the root apical meristem have been identified. Several phytohormones have long been known to affect root growth; it now appears that they have at least one common entry point into the transcriptional networks that regulate root growth. A map of gene expression in the Arabidopsis root has identified many new candidate genes that feed into and out of these transcriptional controls.