Whiteflies possessing unusually high levels of resistance to a wide range of insecticides were discovered in 2004 while conducting resistance surveys in Arizona. A sample collected from poinsettia plants were subsequently confirmed to be the first Q biotype of Bemisia tabaci to be detected in the New World (Dennehy et al. 2006). The strain of Q biotype, named Poinsettia'04, was highly resistant to insect growth regulators as well as neonicotinoid insecticides that have provided the foundation for a decade of whitefly resistance management in Arizona. Surveys conducted in 2005 detected Q biotype whiteflies in over 20 states throughout the USA. However, no Q biotypes have been detected outside of protected (glasshouse or screenhouse) environments. Laboratory studies indicated that the Q biotype may be at a developmental disadvantage, relative to the common B biotype found in Arizona. Severe economic losses to agriculture in many areas of the USA resulted from introduction of the B biotype of B. tabaci. Thus, the potential threat posed by the establishment of multiply-resistant Q biotype whiteflies is indisputable. However, it is not possible to predict with accuracy the future spread of the Q biotype in the USA, or the severity of associated control and virus problems. Research to assess this risk is critically needed, as are contingency plans for its management in vulnerable commodities. Selective insecticides effective against the Q biotype are will be indispensable for integrated management of this pest. 1) T.J. Dennehy et al, 2005. http://cals.arizona.edu/pubs/crops/az1382/az1382_2.pdf.