The reviewer is head of a Central Animal Laboratory of a Medical Center, where about 140 researchers, chiefly M.D.'s work on 11 species: monkeys, dogs, cats, calves, pigs, sheep, rabbits, guinea pigs, rats, mice and gerbils. In 1984 there were 120 licence projects with 32.000 experiments, 74% were carried out on mice, 24.6% on rats and the rest on the other species. Approximately two third of all animals were used for in vitro studies. Each researcher has to apply for a licence for a limited project by giving the title, a brief description of the method, his reasons for wanting to do the experiment and the value of the expected results, and the exact number of animals required. Details of the planned experiments are discussed with the staff of the Central Animal Laboratory. All information is filled in by the responsible researcher on a nation-wide standardized form. The completed form is signed by the head and forwarded by the secretariat to the Cantonal Veterinary Department. Four copies are submitted of which one goes to the Federal Veterinary Department. All applications for a licence are handled by the cantonal veterinary officer. The decisions are controlled by a Cantonal Commission for animal experiments, consisting of 8 members out of which 4 are animal protectionists. In addition the Department of Education has set up a bioethical commission consisting of 4 members of the university, one from the veterinary faculty, two from the medical faculty and one from the life sciences. This commission can also be called on by a researcher if he needs to clarify points before the application is submitted. The animal protection law requests the cantonal veterinary officer to make a thorough check of the project which often demands one or more letters asking for further information. He has to check whether an animal experiment is necessary at all, whether the experiment is properly designed, whether animals of lower order could be used and whether the demanded number of animals is needed. After a project has been completed or every year for a larger project, the number of animals used in the project has to be reported to the cantonal veterinarian who will prepare statistics on total number of animals used. A division of the experiments into in vivo and in vitro experiments will be prepared and categorization according to the estimated degree of stress and pain is being considered.