Loeselia clade is an obscure and little studied lineage in the flowering plant family Polemoniaceae, which includes Loeselia L., Dayia J.M. Porter, and several species previously included in other genera. In spite of the absence of broad comparative studies, Loeselia has played a pivotal role in hypotheses concerning the origin of temperate members of Polemoniaceae. I have developed a research program to better understand the Loeselia clade (with approximately 22 species). Preliminary studies provide evidence that this group is monophyletic. I am currently seeking funding from the National Science Foundation (REVSYS: Relationships, Diversification, and Monographic study of the Poorly-known Loeselia Clade (Polemoniaceae). to support the completion of this research. Exhaustive taxon sampling within the Loeselia clade and dense sampling of related groups will be used to develop a phylogenetic hypothesis of relationships, based upon chloroplast and nuclear DNA sequence, macromorphological, and micromorphological data. This phylogenetic hypothesis will guide taxonomic revisions for this much-neglected lineage at the generic level and comprehensive monographs of Loeselia and Dayia at all levels. My study is both hypothesis-driven and comparative in nature, with multiple, clear objectives. These include testing taxonomic hypotheses, characterizing changes from outcrossing to self-pollination in self-incompatible (a self-recognition system that promotes outcrossing) and self-compatible lineages, and it correlation with variation in floral morphology. My approach will be to use data gathered from herbarium visits and loans to inform a carefully planned series of field trips that will be undertaken to obtain material of little known and poorly collected taxa in southern Mexico, Central and northern South America. Preliminary studies indicate that the targeted genic regions, morphological characters, and analyses to be used will permit me to achieve my goals and objectives.