Biodiversity is a valuable, but poorly understood, natural resource, which is being lost at an accelerating rate as a result of human actions. We present a broad, introductory review of biodiversity concepts. Biodiversity is first defined at the species and community levels. Available methods and approaches for quantifying biodiversity are discussed with specific reference to the spatial scales over which these measures can be applied. Dominant threats to biodiversity are reviewed. Fundamental patterns and processes that underlie ecological production functions are outlined. Differing rationales for biodiversity conservation are given and compared. Finally, the current suite of approaches employed in biodiversity conservation is discussed. Our aim in writing this review is to encourage further, much needed, inter-disciplinary collaboration among economists and ecologists on biodiversity questions.