Movement of cutthroat trout in three small coastal streams was studied from October1959 to December 1963. Upstream migrations of trout occurred from late October until March,with a maximum in December. Kelts returned downstream from December to April with thegreatest numbers in January and February. More than 90% of the downstream movement ofimmatures occurred in February, March, April, and May, with numbers being consistently greatestin April. Two-year-old immature fish dominated the run in the two larger streams, while 1-year-oldimmatures did so in the smallest stream.Small tributaries of the study areas were found to be very important to cutthroat troutreproduction. Young trout were noted to leave the tributaries at about 1 year of age. Trout 150mm in length that had never left the study streams were found in a gravid condition near reddsites.