<p>Birds behave as if sheet glass is invisible to them. They kill themselves striking clear and reflective panes in all types and sizes of human-built structures the world over. The killing is indiscriminate, taking the fit and unfit species, of any age category- both common and of conservation concern. Window-kills occur in the billions worldwide annually. The victims are always unintended, unnecessary, harmless, and have no voice or other means to protect themselves.</p><p><br></p><p>The science documenting this significant scale of loss has been known for decades, but only recently have meaningful efforts to address the problem occurred. Here, Dr. Daniel Klem, Jr., describes and summarizes the challenges and solutions to this important conservation issue for birds and people that can be used by, among others, architects and developers, legislators, legal professionals, urban planners, and homeowners alike.</p><p>Unlike the complexities of other environmental challenges, such as clim