"Threshold concepts" are concepts that, among other things, transform the way a student looks at a discipline. Although the term "threshold" might suggest that the transformation occurs at a specific point in time, an "aha" moment, it seems more common (at least in computing) that a longer time period is required. This time period is referred to as the "liminal space". In this paper, we summarise our findings concerning how computing students experience the liminal space and discuss how this might affect teaching. Most of our findings so far relate to software engineering. As it is likely that similar liminal spaces occur in other engineering disciplines, these findings have relevance across engineering education.