HOST is a framework, a springboard, for leadership development innovation to help leaders, teams and organisations transform, thrive and lead in complex and fast changing environments. This Guide contains the definition of HOST. This definition consists of HOST’s roles, practices, meta-skills and the rules that bring them together. Jessica Tangelder developed HOST; the HOST Guide is written and provided by her and closely reviewed by the HOST Board of Experts. Together, they stand behind the HOST Guide.