Cilia are essential for normal organ function and developmental patterning, but their role in injury and regeneration responses is unknown. To probe the role of cilia ininjury, we analyzed the function of foxj1, a transcriptional regulator of ciliagenes, in response to tissue damage and renal cyst formation. Zebrafish foxj1a, but not foxj1b, was rapidly induced in response to epithelial distension and stretch, kidney cyst formation, acute kidney injury by gentamicin, and crush injury in spinal cordcells. Obstruction-induced up-regulation of foxj1a was not inhibited by cycloheximide, identifying foxj1a as a primary response gene to epithelial injury. Foxj1 was also dramatically upregulated in murine cystic kidney disease epithelia [jck/jck (nek8) and Ift88Tg737Rpw-/-] as well as in response to kidney ischemia-reperfusion injury. Obstruction of the zebrafish pronephric tubule caused a rapid increase in cilia beat rate that correlated tightly with expanded tubule diameter and epithelial stretch. Zebrafish foxj1a was specifically required for cilia motility. Enhanced foxj1a expression in obstructed tubules induced cilia motility target genes efhc1, tektin-1, and dnahc9. foxj1a-deficient embryos failed to up-regulate efhc1, tektin-1, and dnahc9 and could not maintain enhanced cilia beat rates after obstruction, identifying an essential role for foxj1 inmodulating cilia function after injury. These studies reveal that activation of a Foxj1 transcriptional network of ciliogenic genes is anevolutionarily conserved response to multiple forms of tissue damage and highlight enhanced cilia function as a previously uncharacterized component of organ homeostasis.