Growth in total body length and weight was described for lake whitefish, Coregonus clupeaformis (Mitchill), taken in the commercial fishery at Red Lakes, Minnesota. Growth was among the fastest when compared with that reported for other North American waters. Growth rates of males and females were similar until the end of the fourth year, but in the fifth and later years, females were slightly longer. Females reached a maximum age of 9 and males 8. Five-inch-mesh nets, fished in the fall, captured faster-growing members of age groups III and IV than the 3 1/2-inch-mesh nets fished in the summer. Fish taken in June were heavier (dressed weight) than fish of similar lengths in July and August. Records of catches and fishing effort of the fishery were described from 1917 to 1963. Great variability in age composition of commercial catches was associated with variability of strength of year classes. The 1954 year class was the major contributor in both numbers and weight to the fishery for 5 years, and was approximately 160 times stronger than the weakest year class. Strength of whitefish and walleye, Stizostedion vitreum vitreum (Mitchill), year classes were related, but no correlation of year class strength with various physical factors was found. The fishery contributed to a high annual total mortality of 70% for age II and III fish.