Raspberry bushy dwarf idaeovirus (RBDV) is the cause of yellows disease and crumbly fruit in sensitive cultivars of raspberry and blackberry. In most of Europe, the UK, USA and Australasia, control of the virus has been successfully achieved for more than 40 years through cultivation of immune cultivars. The recent occurrence in commercial raspberry crops in the UK and some European countries of this virus isolates able to overcome this immunity, poses major problems for its control. Research initiatives made in response to the new situation are presented. Reversion disease of blackcurrant is the most important disease of this crop worldwide. The disease agent is transmitted by the blackcurrant gall mite, Cecidophyopsis ribis, but the nature of the agent is not known. Strategies to control both the mite vector and the disease in plants by introducing genes for resistance are described, together with possible problems associated with such strategies.