Ethnobotany, as a scientific discipline, deals with humanplant relationships, and is vitally important to plant conservation. Ethnobotany is used in many countries throughout the world for documenting indigenous knowledge of plants. Consequently, many inventories of useful plants in local floras have been compiled. Over the last hundred years, local knowledge about plants, gained through ethnobotanical studies, has contributed greatly to the development of medicine and agriculture, and to the discovery of numerous new plantbased products. Since the 1960s, the scientific community has become increasingly aware of the magnitude of global environmental change, now occurring at a speed never before encountered in human history. Natural resources are being depleted at an alarming rate and there are threats of imminent extinction to many species. Faced with this crisis, ethnobotanical research assumes a new urgency, not only as a tool for trying to deal with environmental degradation, but also for its potential usefulness in contributing to sustainable use of plant resources and poverty reduction among rural communities. Ethnobotanical research can contribute to modern development in many ways, including: creating information/databanks of traditional knowledge about plants for use in conservation and future development; managing the landscape so as to best deliver conservation benefits of all types; enhancing rural community engagement in rural development. This paper discusses ethnobotany and its role in modern development and biodiversity conservation, the challenges that biodiversity and sustainable use face,and the biocultural approach of biodiversity use and conservation.