Sponsors face significant challenges in the development of biosimilars, particularly in the chemistry, manufacturing, and controls (CMC) aspects. Key areas of biosimilar CMC development include establishing a reliable and consistent manufacturing process, controlling critical quality attributes, and developing analytical methods to assess product quality. Furthermore, sponsors must conduct extensive characterisation studies, encompassing physicochemical and functional assays, to demonstrate biosimilarity between the biosimilar and the reference medicinal product (RMP). This article provides insights from a sponsor’s perspective, highlighting the challenges and opportunities associated with the biosimilar CMC development process. By adhering to these recommendations, sponsors can navigate the complexities of biosimilar development and enhance the likelihood of successful outcomes.