Faced with the challenge of overproduction associated with the linear economic and consumption model, it is necessary to promote the sustainable transformation of the textile and clothing industry ecosystem. The ubiquitous presence of design in our daily lives serves as both a unifying force and a catalyst for the substantial advances in theoretical and practical knowledge that are required. It embraces cognitive and systemic methodologies while advancing technological capabilities in diverse fields including materials science, process and environmental engineering, biotechnology, manufacturing systems, information technology, and the spectrum of social and behavioral sciences. This document discusses and reflects on the role of design in the textile bioeconomy as part of a professional internship at CITEVE (Technological Centre for the Textile and Clothing Industry). It was carried out as part of the Master's Degree in Design for Sustainability at the University of Lisbon and took place between February and August 2023. During the internship, the master’s student actively contributed to four projects described in this document. These projects were part of the be@t – Bioeconomy at Textile Project, which aims to strengthen the Portuguese bioeconomy, and the Waste2BioComp Project, which focuses on the transformation of organic waste into sustainable bio-based components. This internship experience contributed to the development of transdisciplinary professional skills and exemplifies a commendable integration of academic rigor and practical application, contributing to a promising path for sustainable progress in the textile and clothing industry in Portugal