Biologists have been testing wildlife contraceptives in the field for nearly a half century. Although effective new contraceptive agents have been identified, new delivery technologies developed, and some success with population management demonstrated, progress in this area should be further along. Why is it taking so long? First, the task is complex. Most drugs and vaccines fail in development. The technical leaps from in vitro to in vivo, from controlled studies to field studies, from effectiveness in individuals to management of populations, are all formidable and frequent failures are inevitable. Testing the long-acting contraceptives required for successful population management demands experiments that take 3–5 yr to complete. Development of wildlife contraceptives has been further hampered by the lack of large-scale investment and the complex and shifting regulatory landscape that often greets novel enterprises. But there has also been focused resistance to the implementation of wildlife contraceptive studies and to the dissemination of results such studies have produced. This phenomenon, which sociologists label “socially constructed ignorance,” has taken a variety of forms including denial of research permits, omission from research reports and management documents, and repetition of misleading or false information in public forums and the media. The persistence and effectiveness of this social resistance suggest that the ethical foundation of wildlife contraception is incomplete. As the institutional affiliations of participants of the 7th International Conference on Fertility Control for Wildlife confirmed, wildlife contraception has its ethical roots in the animal welfare and integrated pest-management communities. Absent from the discussion are the conservation community and the values they represent. To secure societal acceptance of wildlife contraception as a management technique, researchers and advocates for wildlife contraception must address conservation issues and build an ethical foundation that balances concern for individual animals and human needs with concern for the health of biologic communities.