Abstract: Floral diversification in Pedicularis (Orobanchaceae) is remarkable among flowering plants. In this paper, we summarize previous studies and discuss recent research into floral diversification and reproductive adaptation in this genus.Developmental studies of Pedicularis reveal that the ontogeny of the four general corolla types is similar in the initiation of floral organs, whereas meristem activity on the upper lip plays an important role in corolla architecture and may have significant contributions to floral differentiation. Palynological studies reveal that floral types are strongly as sociated with pollen aperture types : 95.2% of long- tubed species were found to be bisyncolpate, as compared with 22.2% in beakles s and toothless species.Pollen aperture evolution may be assoc iated with reproductive adaptation at high altitude. Recent molecular phylogenetic analyses indicate that floral characters have a high degree of parallelism, and morphologic ally similar corollas were apparently derived independently multiple times, perhaps as a result of adaptive radiation. Long corolla tubes were derived from short ones, galea teeth were derived from toothles sgaleas, and the diverse forms of galea beak were both gained and lost over the course of floral evolution. Field pollination studies demonstrate that corolla type and bumblebee (Bomb us Latr .) pollination behavior are highly as sociated. Species with similar corollas are visited by diverse pollinators with similar foraging patterns, but pollen is apparently deposited in different positions on different pollinators, thus promoting reproductive isolation among sympatric species of Pedicularis.In addition, the differentiation of floral characteristics may have accelerated speciation in Pedicularis.