Contents: Introduction. 1. Important ethnic/tribal communities. 2. Ethnobotanical resources. 3. Ethnofood: 1. Wild plants: i. Young leaves and twigs. ii. Flowers and inflorescens. iii. Fruits. iv. Seeds. v. Roots, rhizomes and tubers. 2. Cultivated plants: i. Cereals, pseudocereals and pulses. ii. Vegetables. iii. Fruits. iv. Condiments. 4. Ethnomedicine. 5. Fibre and floss. 6. Oils: i. Fatty oils. ii. Essential oils. 7. Dyes. 8. Gums and resins. 9. Fish poisons. 10. Insecticides. 11. Timber and woodwork. 12. Tannins. 13. Baskets brooms and mats. 14. Fodder plants. 15. Fuel woods. 16. Plants for religious ceremony. 17. Miscellaneous. 18. Potential threatened ethnomedicinal plants and their conservation. 19. Ethnopharmacological screening. 20. Tribal development. 21. Discussion and conclusion. References. "Under an approved in house research project of National Botanical Research Institute (NBRI), Lucknow, ethnobotanical studies of the tribals and aboriginal populations were conducted in 13 districts of Uttar Pradesh and Uttaranchal inhabited by 18 tribes mainly among the Tharus, Kols, Gonds, Bhoxas, Kharwars, Jaunsaris, Bhotias, Garhwalis, Mushars, Baigas etc. in different seasons with a view to gather ethnobotanical informations on the traditional uses of plants and to uncover new plants of potential economic and medicinal value or new uses of known plants during the last 18 years by the scientists of ethnobotany group.