Human beings and their activities have increased the changes occurring in the environment. Until recently the arrival of new organisms into geographically isolated environments was a rare event. Modern means of transportation have broken old geographic boundaries. Non-native organisms, when introduced to a new area, can out-compete native species, cause disease to, or destabilize and occasionally ultimately wipe out native species. Invasive species constitute a threat for biodiversity at the local and regional levels, since the spread of newcomers can alter the richness and abundance of the flora and fauna of the original ecosystem. As a result, native species are abruptly faced with new species and new environments with which they have had no evolutionary history.Some species have developed the capacity to adapt to new sites and to displace original populations. This phenomenon has been widely recorded and it is known as 'biological invasion.' Many non-native plants have allowed increasing productivity in agriculture, becoming a fundamental part of human economy, whereas others have developed into serious ecological problems. However, besides (a) non-native plants, potential biosafety risk factors comprise two additional groups: (b) taxa resulting from traditional breeding, and (c) genetically modified plants (GMPs). The term 'biosafety,' defined as the prevention of large-scale loss of biological diversity and integrity due to human activities1, has been often reduced to potential risks due to GMPs. However, non-native plants and pathogens, taxa resulting from traditional breeding and also GMPs are important issues for the biosafety sector.