Dangerous ideas are those that challenge the status quo, ignore political correctness or, if followed, lead to an unsettling series of consequences (Pinker 2006). As practising zoologists, our ongoing concern relates to the long-term survival of our native wildlife across all land tenures and the marine environment, and protecting natural areas in perpetuity. We hoped that a day of dangerous zoological ideas would stimulate fresh thinking and discussion about how to meet the challenges in using science to help conserve wildlife in the 21st century. While we as editors have a view on what comprises a dangerous idea (and a solid zoological idea), we were most reluctant to circumscribe our speakers and their papers. As a consequence, the papers in this volume reveal a remarkable take on what is dangerous, or at least what is considered dangerous and by whom. Some authors pose dangerous new ideas to solve difficult zoological challenges, others highlighted dangers in the misinterpretation of science and make a call for change, while others revealed hidden dangers in zoological ideas that are popular with the public but are yet to be fully thought through. Collectively the papers in this volume reveal that within the discipline of zoology, the battleground of ideas is awash with tough contests. Here though, our focus is on understanding and conserving our native fauna and, to that end, the Royal Zoological Society of NSW is keen to be dangerous in a world locked more into economic growth than an appreciation of our natural heritage and how to conserve it.