Monitoring parallel to cultivation is required for genetically modified plants in the EU.
Under the terms of the amended release directive (2001/18/EC), a post-release monitoring plan must accompany applications for cultivating GM plants.
Authorisation is contingent upon a parallel, general monitoring plan, which in some cases can include special stipulations addressing crop-specific areas of concern.
The purpose of monitoring is to identify unforseen effects of large-scale GMO production on the environment. It can also be useful for determining if potential negative effects noticed during safety assessments actually cause problems.
Monitoring is also used to develop and validate co-existence measures.