The goal of this study was to explore the prevalence with which Australian Western herbalists treat menstrual problems and their related treatment, experiences, perceptions, and interreferral practices with other health practitioners ⁽¹⁾. Members of the Practitioner Research and Collaboration Initiative practice-based research network identifying as Western Herbalists (WHs) completed a specifically developed, online questionnaire. Western Herbalists regularly treat menstrual problems, perceiving high, though differential, levels of effectiveness. For menstrual problems, WHs predominantly prescribe individualised formulas including core herbs, such as Vitex agnus-castus, and problem-specific herbs. Estimated clients' weekly cost (median = $25.00) and treatment duration (median = 4-6 months) covering this Western herbal medicine treatment appears relatively low. Only 19% of WHs indicated direct contact by conventional medical practitioners regarding treatment of clients' menstrual problems despite 42% indicating clients' conventional practitioners recommended consultation with WH. The authors conclude that Western herbal medicine may be a substantially prevalent, cost-effective treatment option amongst women with menstrual problems.