This video by Charlie Heriot-Maitland, Kings College London, is a great example of Compassion Focused Therapy (CFT) in action. It illustrates how CFT can help to work with the voices in our heads, whether we recognise these as our own (eg internal critic, anxious mind or so on) or as coming from someone else/an external source, as in the case of Stuart.
A great introduction to CFT ideas and practice.