On the Cover: Chamaecrista fasciculata, an annual North American prairie legume, is emerging as a model for the nonpapilionoid legumes. C. fasciculata belongs to the paraphyletic subfamily Caesalpinioideae within the mimosoid clade. Mimosoids diverged from the papilionoids (including the models Medicago truncatula, Lotus japonicus, and Glycine max) nearly 60 million years ago—nearly contemporaneously with the origin of legumes. There is growing interest within the legume community in C. fasciculata as a complementary legume model for a number of reasons, including phylogenetic position, wide ecotypic diversity, nodulation within a clade of limited nodulating species, nonpapilionoid floral morphology, herbaceous growth habit, and tractability in laboratory and field settings. Whole-transcriptome sequencing of C. fasciculata shoots, roots, and nodules, along with gene expression profiling and SNP profiling, provides community resources to address fundamental questions about legume evolution. A range of characterized ecotypes, development of functional genomics tools, and integration of research and undergraduate education leverage these genomic resources. Cover image by Steven Cannon. (See Singer et al., pp. 1041–1047.)