The term "accessibility" is broadly used to describe the degree to which a service or product gives learners the "ability to access" functionality, services or materials. In recent years there has been a push towards accessibility in technology-enhanced learning (TEL) across all levels of education. However, accessibility represents a shifting frontier. As technology evolves, so too do issues of equality and access. In this article, the author reviews key developments in accessibility discourse and research to demonstrate the value of attending to accessibility's cutting edge in mainstream TEL practice.