“Books on leadership risk to exaggerate either in theory or in storytelling. de Summa is different. For those who fear theory, there are a lot of small cases and hints, and for those who are a Leo Neelslittle suspicious towards cases only, there is a continuous conceptual flow that stands in its own right.

de Summa is a rare combination of insight and experience, of pragmatism and analysis, of sharing praxis and building understanding of the underlying dynamics. Moreover, de Summa is written in a vivid and fluid semantic style that incites the reader to turn the pages.”
Prof dr Leo NEELS, President Press Agency Belga, President Adv. Board AMS Family Wealth Institute.



“It is a thrill to discover that all of this can be captured in mere words and simple images. Read the book, be amazed by its elegance and then (re)write your own.. Your copy won’t be ‘de Summa’, but do not let that disappoint you too much. Jointly they’ll be the perfect pair for you. “
Francis Arickx, Directorate Head, National Institute for Health & Disability Insurance; Lecturer Health Policy, University Antwerp.



Krisja Vermeylen“Being appointed as a leader is one thing, making a difference as a leader is something else. If you are interested in the latter, read this book to find valuable insights created by the mix of leadership theory and more than 25 years hands-on leadership experience. Concrete tips and tricks can move you and your organisation to a higher level. The more you dive in this book, the more you like it.”
Krisja Vermeylen, Sr Vice-President, Novo-Nordisk“


Jef Brouwers

Leadership and management books tend to end up on the shelf. This book is a roadmap on leadership and organizations that you will want to keep close to you for a daily dose of wisdom.”
Jef Brouwers, Vice President European Operations , CRC Industries Europe



maes ingrid

“De Summa is an excellent tool to be considered as the ‘formularium’ for leadership in action. In combination with Geri’s coaching excellence, it is what you need to get to the next level in leadership and teamship.”
Ingrid Maes, Managing Director & Co-Owner, Inovigate



Alix Engalytcheff

“de Summa succeeds in covering 2 complementary perspectives of the journey to leadership. It provides numerous stimuli for reflection and at the same time very practical techniques to adapt straight away. It works. You’ll become a better manager, a better leader, and maybe a better person.”

Alix Engalytcheff, PhD, Western Europe Market Access Director


“This masterly book makes a significant contribution to the field of leadership. People Dirk Van Pouckeleading organizations will benefit greatly from this lucid book and its fascinating insights. A quality of framework that make it an extraordinarily source of guidance.”
Prof. dr. Dirk Van Poucke, Flanders Business School; Law Firm Storme, Leroy & Van Parijs; NEGO bvba


Luc Debruyne“If you are still wondering what and how leadership and great teams can bring value to your business, then read this book. It offers provoking quotes, formats and insights , but at the same time invites you to ‘think twice’ ! ”
Luc Debruyne, President GSK Vaccines


Griet Nuytinck


“This book will become a good and loyal friend, the company you need to lead.”
Griet Nuytinck, CEO Anacura


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