In plants, flowering is triggered by endogenous and environmental signals. CONSTANS (CO) promotes flowering of Arabidopsis in response today length. Four early target genes of CO were identified using a steroid- inducible version of the protein. Two of these genes, SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) and FLOWERING LOCUS T (FT), are required for CO to promote flowering; the others are involved in proline or ethylene biosynthesis. The SOC1 and FT genes are also regulated by a second flowering- time pathway that acts independently of CO. Thus, early target genes of CO define common components of distinct flowering-time pathways.