Separating from our thoughts often involves thinking about our own thoughts (meta-cognition). We describe meta-cognitive processes relevant to how individuals calibrate and control the impact of their thoughts on judgement and behaviour. Amongst other things, this special issue presents us with an opportunity to examine the similarities and differences between key contributions focused on correction and suppression processes, decentering approaches and separating from thoughts by using a variety of techniques. In addition to these paradigms covered in the articles of this special issue, we review other approaches that also involve reducing the impact of thoughts, with special attention to invalidation processes. Additional frameworks relevant to mental separation included in this review are those relevant to non-evaluative observation of thoughts, psychological distance and mental hygiene.