This report deals with the migration of wild brook trout and brown trout, over 7 incheslong, in the Hunt Creek and upper Au Sable River systems. Between 1934 and 1967 we jawtagged3,320 brook trout, 5,615 brown trout; anglers reported catching 346 of the brook trout, 480brown trout. Brook trout were recaptured close to where they had been tagged and released –91% within one mile, the remainder within 11 miles. Migration of brown trout (in the Au Sablesystem) was more variable. Seven to 13 inch browns stayed mostly (75-88%) within one mile oftagging sites. Most browns over 13 inches in the North and South Branches Au Sable migratedseveral miles (some up to 10 to 40 miles), but in the Main Au Sable 90% of the big browns wereless than one mile from tagging site. Spring-tagged trout gave 1.8 times as many returns as falltagged fish. Brook trout recoveries were 97% within the first year after tagging; whereas 67% ofthe reports for browns came within the first year, and 33 after 2 to 5 years.