There is confusion in the terminology used to describe different forms of cognitive behaviour therapy, in particular low intensity CBT. Such confusion has implications for research, clinical practice and service organisation. This thought-piece aims to describe the key components of low intensity CBT in comparison to brief high intensity standard CBT. It is proposed that low intensity CBT (i) utilises self-help materials, (ii) is six hours or less of contact time with each contact being typically 30 minutes or less, and (iii) any input can be provided by trained practitioners or supporters. These components distinguish the intervention from brief high intensity intensity CBT which (i) is based on the standard evidence-based CBT treatment, with therapy contact time 50% or less than the full CBT intervention, and (ii) is usually delivered by someone with a core mental health professional qualification or equivalent. Brief CBT can refer to either low intensity CBT and/or brief high intensity CBT. We hope that making the distinction between these different forms of intervention stimulates debate and helps consistent and appropriate categorisation for future research and practice.