Like the human immune system, a biosecurity system is a constellation of responses to external attacks comprising of many facets, a number of which can change to optimize the response to these unwanted intrusions. When either system hits the wrong target, or is inhibited or crippled somehow, the consequences for the body and the economy can be dire. Like an immune response, an effective response to an invasive alien species incursion may be the result of a series of failed attempts or past experiences rather than being perfect the first time. In view of the enormously complex environment in which responses are made, this paper discusses institutional changes that may facilitate an adaptive approach to biosecurity policies where governance is viewed as a multi-disciplinary, interactive experiment acknowledging uncertainty.