Agastache is a genus of perennial plants in the mint family primarily native to North America. This genus produces aromatic oils that are used in foods, drugs, and perfumes. Agastache has also been reported to be a valuable source of nectar for honey bee forage. The genus has gained importance in America, Asia, and Europe as a component of tea mixtures and as a flavoring in confections. Because of the increasing popularity of this genus and our limited base of knowledge about it, this dissertation project was conducted to address questions of how aromatic compounds and isozymes are inherited in A. foeniculum. In addition, the genetic control of anthocyanin production and malate dehydrogenase was investigated in A. rugosa;A comprehensive review of research investigations on the genus Agastache is presented. The review covers morphologic, cytogenetic, and taxonomic studies of Agastache. It also includes references describing biochemical studies of Agastache and others describing the culinary, pharmaceutical, and ornamental applications of this genus;I conducted studies to determine the inheritance of some common aromatic compounds and of isozymes in A. foeniculum. Controlled crosses were made between individuals with different chemotypes and isozyme banding patterns and their F2 progenies were analyzed. Hypotheses describing the genetic control of the production of myrcene, limonene, and methylchavicol and of Cat, Got-2, Pgm-2, Tpi-1, and Tpi-2 were tested. In general, production of the three aromatic compounds controlled by single genes with dominant alleles. Results also revealed that Cat, Got-2, Pgm-2, Tpi-1, and Tpi-2 are each controlled by a single gene with codominant alleles;I also conducted a study to determine the inheritance of anthocyanin production and of malate dehydrogenase banding patterns in A. rugosa. These data also support the hypothesis that each of those traits is controlled by single genes. This is the first report of heritable variability in A. rugosa. In general, the genetic behavior of Agastache is that of a normal diploid species.