According to the ISI Web of Knowledge, the 2008 impact factor for SLEEP is 4.475, and the five-year impact factor is 5.236. Among journals that publish original scientific discoveries, the impact factor for SLEEP is the highest.

The impact factor of SLEEP has continuously risen over the past decade; in 1998 the impact factor was 1.880 and in 2000 it was 3.168. The continued excellence of SLEEP is a testament to the high standards of the journal, which is the authoritative source for research on sleep and sleep disorders.

All members are welcomed and encouraged to submit their original sleep science for consideration. Please visit for details.