The Panel on Plant Health conducted a pest risk assessment for Bemisia tabaci and the viruses it transmits, including an evaluation of risk reduction options and an assessment of the effectiveness of the special requirements linked to B. tabaci and the viruses listed in Council Directive 2000/29/EC. B. tabaci and a large number of viruses transmitted by this polyphagous insect occur in subtropical and tropical climates around the world. Five entry pathways for B. tabaci and associated viruses were identified, with the plants for planting pathway being most significant and rated for entry of insects and viruses as likely and moderately likely, respectively. The most invasive B. tabaci species and several of its associated viruses responsible for severe diseases in major European food crops are established outdoors in coastal Mediterranean regions. Because of similar climate requirements and host plant preferences, B. tabaci and associated viruses currently not present in Europe are likely to establish within the temperature limits set for B. tabaci. Trade between European Member States allows B. tabaci to reach greenhouses in northern Europe, including those in areas with protected zone status. Because of the cool climate, establishment and spread outdoors of B. tabaci is rated unlikely for northern Europe. This situation is likely to continue even under a climatic scenario with an increase in temperature of +2 °C. B. tabaci -transmitted viruses cause severe diseases with major negative impact on crop production when risk reduction measures are not used. Risk reduction options will also apply to B. tabaci and viruses new to Europe. Risk reductions options are evaluated in terms of reducing B. tabaci populations, crop infestations, virus incidence and the impact of diseases. © European Food Safety Authority, 2013