White clover is a main forage Iegume in temperate regions in the world. Alfalfa mosaic virus (AMV) is one of the most important viral diseases affecting white clover production, causing significant economical losses. In order to address this issue, AMV-resistant transgenic white clover has been developed. Before any deliberate release of a genetically modified (GM) white clover, biosafety studies associated with the insertion of the novel gene need to be undertaken to assess possible risks to animal or human health and to the environment. Some of the areas that need to be studied are potential toxicity and allergenicity of the genetically modified organism (GMO), as well as gene flow under field conditions. Nutritional composition and levels of natural toxicants (cyanogenic glucosides, phytoestrogens and saponins) commonly present in white clover were conjunctively assessed in AMV-resistant transgenic lines and corresponding wild-type counterparts. No significant differences were found between the AMV-resistant transgenic white clover lines, their corresponding wild-type counterparts and commercial white clover cultivars. Gene flow in white clover under field conditions was assessed in a two year study using a dominant red leaf mark in donor plants as a phenotypic indicator of effective pollination over distance. A 400 m2 central pollen donor plant plot was surrounded by 8 peripherical spokes where recipient plants with no leaf marking were positioned at distances to up to 200 m away. Progeny plants were scored for the red phenotype and gene flow was modelled. SSR polymorphism was used to identify paternity of progeny. Gene flow showed a leptokurtic distribution under conditions designed to maximise gene flow from donor to recipient plants. Most gene flow occurred within the first 50 m; however, some red leaved progeny were still detected at a distance of 200 m.