Thebo is a small Tibetan dialect spoken at the border of Sichuan and Gansu Provinces, China. The morphosyntactic structures that express egophoricity and evidentiality in Thebo Tibetan differ from those of other Tibetan dialects in that they involve both dedicated markers and stem alternations. This work examines how egophoricity and evidentiality are realised in Thebo using first-hand fieldwork from the variety spoken in Gyi.ba Town. It presents both synchronic and diachronic analyses, and considers how the distribution of egophoricity markers reflects the grammaticalization of these categories.