Previous field trial data and field observations on cotton (Gossypium spp.) indicate that both Baythroid and Monitor provide suppression of sweetpotato whitefly (Bemesia tabaci). Field trial data also suggests that the tank mix combination of Baythroid and Monitor can provide additive control of numerous pests. Based on these results, field trials were conducted to determine the effectiveness of a Baythroid/Monitor tank mixture on sweetpotato whitefly. Field trials were conducted during 1992 at Yuma, AZ and Holtville, CA (2 trials). Pest pressure was high at all locations. Weekly foliar applications were made as needed in each trial. The number of nymphs in a given leaf area was used as a measure of control. In the first trial the combination of Baythroid 2 at 0.035 lb. Al/A and Monitor 4 at 1.0 lb. AI/A provided additive control of whitefly. In the second trial, Monitor at a half-rate (0.5 lb. Al/A) in combination with Baythroid at 0.05 lb. AI/A gave equivalent control to a full rate of Monitor (1.0 lb. AI/A) in combination. In a third trial, the Baythroid/ Monitor tank mix combination at 0.035 plus 1.0 lb. AI/A, respectively, provided equivalent control and yield increase (308% over untreated check) to the standard Capture/Thiodan (0.1 plus 1.0 lb. AI/A) and Danitol/Orthene (0.2 plus 0.75 lb. AI/A) treatments.