Part of a toolkit used in the Transforming Perspectives project, looking at using 'threshold concepts' as a framework for identifying areas of conceptual difficulty in disciplinary curricula. This document gives an outline for running a focus group with students to discuss and elaborate on a specific threshold concept, drawing out the student perception of why a particular concept might be a TC, how to approach it and what 'getting it' might mean for them. It is also a useful process for assisting students to identify other threshold concepts.