A whitefly resistance crisis in Arizona in 1995 prompted the development of a resistance management strategy in 1996 that recommended maximal once per season use of each of two insect growth regulators, Knack® (pyriproxyfen) and Applaud® (buprofezin), and limited and delayed use of synergized pyrethroid insecticides in cotton. Implementation of this strategy has substantially reduced the numbers of insecticide applications made to control whiteflies, and statewide monitoring has shown increased whitefly susceptibility to synergized pyrethroids and key non-pyrethroid insecticides. Having benefited from two years of success with this strategy, the Arizona cotton industry now faces the question of whether it can be sustained as Knack and Applaud gain additional registrations for use against whiteflies in vegetables, melons and glasshouse crops. Integrally linked to the current success of whitefly control in Arizona is use of the chloronicotinyl insecticide, Admire® (imidacloprid) as a systemic treatment in vegetables and melons. Plans to register additional chloronicotinyl compounds for use in cotton raise concerns, especially in light of reports of whitefly resistance to imidacloprid in Europe and findings that Arizona whiteflies have become progressively less susceptible to imidacloprid in each of the past two years. Within the context of these new insights we suggest specific actions intended to sustain the current success of whitefly management in Arizona cotton. These involve continued emphasis on limiting the use of IGRs and chloronicotinyl compounds and harmonizing new registrations of these compounds to manage whitefly resistance on an ecosystem, rather than crop-specific basis.