The MEDLINE database is an important resource for locating up-to-date information on herbs and other botanical therapies. However, the evolving nature of complementary and alternative medicine (CAM) and the complexity of herbal terminology can make it difficult to identify useful citations. This paper describes optimal search strategies for finding clinical information on herbs and medicinal plants in MEDLINE using the PubMed retrieval system. Searchers will benefit from an understanding of the structure of Medical Subject Headings (MeSH) and PubMed's advanced search capabilities. Details for using PubMed's MeSH Database, Clinical Queries, Clipboard, and limiting features to retrieve pertinent botanical research are described. Tables containing MeSH terms for medicinal plants and useful print and electronic resources are included.