By Mike Brearley, Ed Smith
By John Maxwell
By Ian Day, John Blakey
By Justin Menkes
By Fred Luthans
By John Wood
By Julie Starr
By Mauricio Vasquez
By Zeynep Aycan, Rabindra N. Kanungo, Manuel Mendonca
By Esther Cameron, Mike Green
By Doris Schedlitzki, Gareth Edwards
By Mike Dent (University of Staffordshire, UK), Swethaa S. Ballakrishnen, Jean-Louis Denis (Ecole Nationale d'Administration Publique, Canada), Tracey Adams
By Stefan Stern, CARY COOPER
By David Jaffee
By Colin Hales (Professor of Management, Westminister Business School)
By Jo Owen
By Thomas Erikson
By Peter Shaw
By Jim Mattis
By Thomas D. Zweifel, PhD
By James M. Kouzes, Barry Z. Posner
By Andrew Rugasira
By Edward de Bono
By Christopher Witt
By Marc Reid
By Joanna Grover, Jonathan Rhodes
By Jonathan Passmore, Association for Coaching
By Julia Hobsbawm
By Stephen Klemich, Mara Klemich, Tommy Spaulding
By Stephen Bungay