A comprehensive review of research investigations on the genus Agastache, sections Agastache andBrittonastrum, is presented. Morphologic, cytogenetic, taxonomic, agonomic/horticultural, and biochemical studies, along with protocols for extraction and analyses of a total of 16 enzyme systems, are analyzed for the 22 morphologically distinct, diploid (haploid chromosome number of n = 9) Agastache species. In addition, the extraction procedures of flavonoids and terpenoids (common constituents of many medicinal plants with biological effects demonstrated in humans or animals) from inflorescences, leaves, stems, and roots of Agastache are surveyed. Details on the safety and uses of methylchavicol (estragole), the main constituent among the 77 compounds reported in the essential oil of Agastache, in the food industry are included and the herbal, flavoring, and medicinal uses of Agastache per se are summarized.