To the extent possible, case studies should be short and succinct summaries of experience on alien species at the country and regional levels. A case-study should focus on the prevention of introduction, control, and eradication of alien species that threaten ecosystems, habitats or species.
Case studies should include the following sections: 1. Description of the problem: (a) Location of the case-study; (b) History (origin, pathway and dates, including time-period between initial entry/first detection of alien species and development of impacts) of introduction(s); (c) Description of the alien species concerned: biology of the alien species (the scientific name of species should be indicated if possible) and ecology of the invasion(s) (type of and potential or actual impacts on biological diversity and ecosystem(s) invaded or threatened, and stakeholders involved); (d) Vector(s) of invasion(s) (e.g. of deliberate importation, contamination of imported goods, ballast water, hull-fouling and spread from adjacent area. It should be specified, if known, whether entry was deliberate and legal, deliberate and illegal, accidental, or natural.); and (e) Assessment and monitoring activities conducted and methods applied, including difficulties encountered (e.g. uncertainties due to missing taxonomic knowledge). 2. Options considered to address the problem: (a) Description of the decision-making process (stakeholders involved, consultation processes used, etc.); (b) Type of measures (research and monitoring; training of specialists; prevention, early detection, eradication, control/containment measures, habitat and/or natural community restoration; legal provisions; public education and awareness); (c) Options selected, time-frame and reasons for selecting the options; and (d) Institutions responsible for decisions and actions. 3. Implementation of measures, including assessment of effectiveness: (a) Ways and means set in place for implementation; (b) Achievements (specify whether the action was fully successful, partially successful, or unsuccessful), including any adverse effects of the actions taken on the conservation and sustainable use of biodiversity; and (c) Costs of action. 4. Lessons learned from the operation and other conclusions: (a) Further measures needed, including transboundary, regional and multilateral cooperation: (b) Replicability for other regions, ecosystems or groups of organisms; and (c) Information compilation and dissemination needed.