Accessibility, usability and inclusion are all important outcomes when developing digital products and services, but previous work and experiences indicate that design practitioners may be confused about the differences between them, resulting in difficulties using them in practice. The study in this paper explores designers’ understanding of these outcomes, using a mini-Delphi method with 11 design practitioners from across two large organisations, who work on the design of new or improved technology to be used by internal and external end-users. The study found that designers are indeed confused about the difference between the terms and identified a need for greater clarity. This paper addresses this by outlining a simple framework for understanding the relationship between accessibility, usability and inclusion, arguing that each should have a distinct and complementary focus. It is recommended that these are addressed systematically, in an integrated way, to develop digital services that address a wider range of user needs across the population.