Circadian clock exists even in peripheral tissues, as well as in the suprachiasmatic nucleus (SCN; the central clock in mammals). About 10% of hepatic genes are transcriptionally regulated in a circadian manner. We found that two types of circadian controlled genes are located in the liver; one type is governed by core components of the circadian clock such as CLOCK and BMAL, and the other is directly dependent on the glucocorticoid hormones secreted from the adrenal gland in a circadian manner. Multiple pathways seem to participate in conveying the time cue from the SCN to peripheral clocks in mammals.