Potato fields in Arlington and Coloma, Wis., were sampled from June through August in 1981, 1982, and 1983, to develop and evaluate the precision of potato leafhopper (PLH),Empoasca fabae(Harris), sampling programs. Midplant leaf samples provided a more reliable estimate of nymphal density than did top or bottom leaf samples. Both Iwao's patchiness regression and Taylor's power law indicated that PLH adult and nymphal counts exhibited aggregated distribution patterns on potatoes. The parameters of Iwao's patchiness regression were used to determine the number of samples required to obtain a standard error of the mean of 0.25. Our sampling procedures achieved this degree of precision at adult and nymphal densities of 3 per 25 sweeps and 5 per 25 leaves, respectively. A sequential sampling plan for PLH on potatoes, based on the parameters of Iwao's regression and using a combination of nymphal and adult counts for the critical density value, was also developed.