The ability of organisms to successfully reproduce in small, isolated populations is a key factor in the generation and maintenance of biological diversity. Reproductive failure due to isolation is a current prospect for many of the long-lived, perennial plants that make up most of the grasslands of the central U.S. because these grasslands now exist mainly as small remnants of a once great prairie. Previous research has suggested that three of the most important causes of reproductive failure in prairie plants are mismatches in the timing of flowering, limited ability to disperse pollen, and mechanisms of compatibility that restrict mating between closely related individuals. In this talk, I will describe our long-term research into these three dimensions of the mating scene in _Echinacea angustifolia_ (the purple coneflower native to Minnesota) growing in 27 remnant prairie population in western Minnesota. I will discuss consequences of reproductive failure for the ecology and evolution of grassland plants and outline current conservation and management concerns.