In 1998, Gordon Sturrock and the late Professor Perry Else presented a paper at the International Play Association Conference in Colorado, USA. The paper was titled ‘The Playground as Therapeutic Space: Play-work as Healing’, later referred to as ‘The Colorado Paper’. The Play Cycle has become established within playwork education, training and professional practice, reflected in the published playwork texts, as well as within the Playwork Principles. However, since the publication of the ‘Colorado Paper’, there have been no empirical studies on its use or playwork understanding of it. Hughes stated that in the 1970s the shift from playleader to play-worker involved the latter to “to turn to the scientific literature to underpin their practice”. In 2006, SkillsActive published ‘The Benefits of Play and Playwork Research: Evidence-Based Research Demonstrating the Impact and Benefits of Play and Playwork’.