The International Council for the Exploration of the Sea (ICES) and the European Inland Fishery Advisory Commission have developed codes of practice on the use of introduced species. These codes generally apply to the purposeful movement of aquatic species, for example, in fisheries, biological control, aquaculture, and for research. There are also guidelines and policy concerning species introduced inadvertently through ballast water or on ships' hulls.

The basic Code (see figure) requires that:

1. the entity moving an exotic species develop a PROPOSAL, that would include location of facility, planned use, passport information, and source of the exotic species;
2. an independent REVIEW that evaluates the proposal and the impacts and risk/benefits of the proposed introduction, e.g. pathogens, ecological requirements/interactions, genetic concerns, socio-economic concerns, and local species most affected would be evaluated;
3. ADVICE and comment are communicated among the proposers, evaluators and decision makers and the independent review ADVISES to either accept, refine, or reject the proposal so that all parties understand the basis for any decision or action, thus proposals can be refined and review panel can request additional information on which to make their recommendation;
4. if approval to introduce a species is granted QUARANTINE, CONTAINMENT, MONITORING, AND REPORTING PROGRAMMES are implemented, and
5. the ONGOING PRACTICE of importing the (formerly) exotic species becomes subject to review and inspection that check the general condition of the shipments, e.g. checking that no pathogens are present, that the correct species is being shipped.

The Code is general and can be adapted to specific circumstances and resource availability, but it should not lose any of the above requirements nor should it lose the rigor at which the requirements are applied. For example, a regulatory agency may require a proposal to contain a first evaluation of the risk/benefits and this evaluation would then be forwarded to an independent review or advisory panel; or the advisory panel could make the first evaluation of a proposal. Similarly, states may require quarantine procedures to be explicitly described in the proposal before approval is granted.