Different methods are used to study the incidence of genetically modified oilseed rape on honeybees, that depend on the type of transgene and on the transformation induced in the plant. Two examples are chosen to present risk assessment procedures.  One deals with oilseed rape resistant to pest insects (by expressing protease inhibitors PI), the other concerns oilseed rape tolerant to an herbicide (glufosinate). In the first case, the aim is to ensure the safety of honeybees. First, the occurrence of the transgene product in nectar and pollen is checked and the foraging behaviour on the plants is observed. Second, the effects of various concentrations, equal or higher than those expressed in the plant, is evaluated under laboratory conditions. Thus, acute and chronic toxicity, individual learning behaviour and life span of workers exposed to the PI is investigated. Experiments are also carried out to examine the effects on the colony activity and development. In addition, indirect effect related to secondary changes in plant signals cueing bees visits are examined. In the second case, the aim is to assess the risk for transgene dispersal in the environment, mediated by honeybees. It is unlikely that tolerance to herbicide has toxic effects, but a pleitropic effect of the transgene could affect the value and attractiveness of the plants. So, pollen and nectar production, flower size and density are evaluated and experiments are carried out in the field to study the foraging behaviour. In particular, the ability of honeybees to cross-visit transgenic and traditional oilseed rape or oilseed rape and weedy relatives is observed. Both types of studies show how complementary methods and collaborations between teams have been designed to study various aspects of the impact of genetic engineered oilseed rape on honeybees.