Founded in 2006, by Vassilis Antonas, Impact is the longest standing Greek firm, specialising in Executive Coaching and Organisational Development. Our company has provided services to over 60 Greek and multinational companies and is the pioneer of the first and longest standing Coaching Training in Greece; the Diploma, which was launched in April 2008 and has run consecutively, every year, since. In 2014, our training was globally the first to receive Accreditation from the Association for Coaching; at top tier (AADCT 4/4).

Our vision is the Evolution of Leadership.

Our mission is to align performance with vision and strategy for individual and corporate leaders.


What: Executive Coaching is the theory and practice of an agent of transformation, supporting a professional’s awareness, leadership and talent, through behavioural and business interventions, within an organisational context. (Antonas, 2017, Coaching for Impact, Routledge, pg 4)

Why: Amongst other benefits, executives and leaders can expect to enhance and improve their pace, resilience, accountability, influence and deliberation.

For Whom: C-level executives, high potentials, management, entrepreneurs, leaders in business.

How:  Coaching comes in clusters of six 45 minute meetings, which can be repeated as many times as necessary. 

  1. A no-obligations chemistry meeting between the executive and our coach. 
  2. kick off meeting between all stakeholders (such as the Head of HR, the line manager if applicable etc) to set expectations and deliverables at the beginning of the engagement. 
  3. Six 45-minute coaching sessions (The cycle of 6 can be repeated). 
  4. A follow up meeting between stakeholders to assess progress at the end of the engagement.

A completely customised 360 will be designed and employed if deemed useful. 

What: The process of aligning collective performance and behaviour with the organisation’s vision and strategy.

Why: To optimise team functioning; to generate common context and direction; to align performance with values, culture and strategy; to foster transformation.

For Whom: Board of Directors, Management Teams, Functional, Sales Teams and Project Management teams. 

How:  A fully customised intervention based on 4 principles: 

  1. Needs assessment based on rigorous data collection.
  2. Cutting edge intervention design based on needs assessment.
  3. Intervention delivery comprising individual coaching, individual and team assessment, workshops, peer coaching, customised 360 surveys and more.
  4. Calibration follow up.

Our workshops are divided equally between skills training, practice and reflection and are based on constant interaction, live feedback and a move-forward attitude. All workshops can be delivered over one or two days for teams of 8-16 leaders and can be customised. Our facilitators all carry OAED LAEK certification and your company can benefit from the the relevant subsidy.

The PRAID Leadership Model

A transformational yet fully applicable leadership model, directly from the field: PRAID combines every possible skill, quality and asset that leaders will need and utilise on their way to the top. Uncompromised and unapologetic, this workshop amalgamates Vassilis Antonas’ work with Senior Leaders over the past two decades and forms the cornerstone of his book, Coaching for Impact (Routledge, 2017). 

Coaching Fundamentals

Coaching can prove immensely useful when done right. It can also be plain counterproductive when done wrong. This workshop is an absolute performance accelerator, since it provides leaders with the fundamental skills that will enable them to coach their teams and their peers with focus and deliberation, whilst avoiding the usual pitfalls.

Conflict Management

Learn the basic platforms of conflict, assess your conflict management style and learn to identify polarities that will metabolise clash into opportunity. An invaluable learning experience that will sustainably enhance collaboration, communication and consequently performance within teams. 

Building Organisational Trust

Mistrust, doubt and suspicion can prove very costly for corporations. In the end, it all tends to form a communication gap that renders collaboration and progress implausible. Our workshop not only practically prescribes how to overcome all that, but also serves as a bridge towards building team spirit and rapport, whilst speeding up delivery. Very few other interventions can match it.

Success Factors in Project Management

Project based work is here to stay. Its effective and strategic management can and will determine profitability, sustainability and business success. Supporting the maturity of individual skill sets and organisational parameters in project management is, at this stage, a one way street. Based on international best practices and global standards like PMI’s and ISO 21500, this training will reform and transform your project managers and their team in an unprecedented way.  

NLP for Business and Personal Transformation.

Timelines, values, anchoring, linguistics, rapport. Enter the world of Neuro Linguistic Programming (NLP), a synthesis of Cognitive and Behavioural Psychology approaches, considered the “manual” of the mind. This manual can be utilised to consistently achieve specific business and personal outcomes. This transformational workshop based on the ABNLP (American Board of NLP) best practices and certifications, focuses on the NLP tools that enable an accelerated transformation of the participants. 


Diploma in Executive Coaching and Organisational Development (AADCT)

Founded in April 2008, our Diploma is the first and longest standing coaching training in Greece. In 2020, our training enters its 13th, consecutive intake. Featuring a carefully selected faculty of expert facilitators, counting over 150 influential alumni and spanning 120 hours of top quality training, in 2014, it was globally the first course to receive Accreditation from the Association for Coaching; at top-tier level 4/4. In 2018, our Accreditation was renewed by the Association for a further 3 years. 

We have been entrusted with transforming leaders from companies and organisations such as Abbvie, Accenture, ALBA, AstraZeneca, BAT, BDO, Center for Democracy, Cognity, DHL, DMG Mori, Evolution Dojo, Eletson, Elval, Fweebi, Great Place to Work, Information Society, Innora, Knowledge Training and Consulting, Microsoft, Mondelez, Nike, PM Partners, Pharmathen, Rigips, Starbucks, Star Channel, Simply Burgers, S & B, Stoiximan, SC Johnson, Unilever, Vestas, Wyeth, 1Source – Aero Services-as well as several consultants, entrepreneurs, journalists, publishers, mental health professionals, project managers, football coaches, martial art instructors and other leaders of transformation.

Course Accreditation:

  • In November 2014 our training program became the first to be awarded Accreditation by the Association for Coaching, globally.
  • The Diploma is accredited at level 4/4, Accredited Advanced Diploma in Coach Training (AADCT), which is the top tier. In 2018, our Accreditation was reviewed and renewed by the Association for a further 3 years.
  • The Diploma is awarded by Impact, an Organisational Member of the Association for Coaching
  • Individual Accreditation can also be obtained upon completing the requested hours of coaching practice and subject to meeting all other application criteria. (Please visit the AC website for more details).
  • Impact can provide supervision towards completing full membership and accreditation requirements.

The course provides 120 hours of Continuous Professional Development Units (CPDU) as indicated on the certificate.


The Corona Virus challenge, has enabled us to evolve and run the course on a web based platform. Should circumstances change, we can return to our host, OTE Academy.

Lunch, coffee and refreshments inclusive

Association for Coaching
Course Dates for 2020-21
MayFriday 8, Saturday 9 + Sunday 10

Vassilis Antonas:
Fundamentals of Executive Coaching & OD
Transformational Leadership: A Jungian Perspective
JuneFriday 12 + Saturday 13
George Diakonikolaou:
NLP Coaching for Impact
Tereza Venetsanou:
Systems & Organisational Development
June to SeptemberStudy Period

SeptemberSaturday 12 + Sunday 13
Suzanne Ferreira:
Leadership and Wellbeing
OctoberSaturday 17 + Sunday 18
Ana Rhodes:
Beyond Conflict
NovemberSaturday 7 + Sunday 8
Renos Papadopoulos:
Leadership Transformation: Surviving and Thriving through Adversity
DecemberSaturday 5 + Sunday 6
Vassilis Antonas:
The Evolution of Leadership: Leading with PRAID
Coaching for Impact: A Complete Method
December to January
Placement Delivery, Presentation Design & Thesis Preparation
JanuarySaturday 16 + Sunday 17
Vassilis Antonas:
Placement Presentations

Click here to access Facilitator’s CVs

Association for Coaching

Entry Requirements

  • Graduate academic qualification
  • 1 year’s experience in OD, Consulting, HR, Counselling or Management
  • Minimum age requirement 25
  • Good command of the English language
  • Personal maturity and capacity to challenge your reflective learning curve

Admission Process

  • Submission of CV
  • Submission of paragraph stating experience and aspirations in coaching and OD
  • Interview with Course Director
  • 50% down payment

We accept an average of 65% of applications received


  1. 3,500 word case study or research: assessed by the Course Director and/or Facilitators and externally validated if necessary or in case of dispute
  2. Attendance (85% minimum required) and contribution
  3. Successful completion of practice/placement and case study presentation (Impact will assist you in finding a voluntary unpaid placement within one of our client companies, but does not guarantee one. The placement can be a team OD intervention or individual coaching. In both cases 3 meetings will be required-one for data collection, one for intervention and one follow up. We have so far secured a placement for all alumni): Peer Assessed.**
  4. Written examination on theory, covering the core material taught and reading list***
*Each one of the 4 assessment areas carries equal weight (25%) and must be successfully passed (60%) to secure a certificate
** In addition a 60 hour coaching practice log must be submitted in order to receive the Diploma as required by the Association for Coaching.
***The Graduation/completion rate is approximately 85%, subject to successfully completing and passing all assessment criteria.

Contact or call +30 2108014505 to receive the complete syllabus

Association for Coaching

Vassilis Antonas

Executive Coach, Psychotherapist, Organisational Development Consultant and
Course Director of Impact’s Diploma in Executive Coaching and Organisational Development (AADCT), globally the first Coaching Training to receive Accreditation from the Association for Coaching. Vassilis is the author of Coaching for Impact: The Evolution of Leadership, published by Routledge in 2017.
He has consulted for over 60 Greek and Multinational companies, delivering tens of thousands of consultation hours to leaders from all functions and industries. Clients include Microsoft, Alcon, Nike, NN, Unilever, Mondelez and more.

From 1998 to 2001, he worked for the British NHS and served as Clinical Director for CAP London from 2001 to 2006, at which point he returned to Greece and founded Impact. His vision is to craft the circumstances for pursuing excellence for individuals and organisations: Directly, by offering Executive Coaching and Organisational Development services and indirectly through the Diploma.

Vassilis is also a composer, a martial arts instructor, a free diver, former motorsport driver and devoted world traveller.

Professor Renos K. Papadopoulos, Ph.D.

Renos Papadopoulos is Professor of Analytical Psychology and Director of the ‘Centre for Trauma, Asylum and Refugees’, also, a member of the ‘Human Rights Centre’, of the ‘Transitional Justice Network’ and of the ‘Armed Conflict and Crisis Hub’ all at the University of Essex, as well as Honorary Clinical Psychologist and Systemic Family Psychotherapist at the Tavistock Clinic. He is a practising Clinical Psychologist, Family Therapist, Jungian Psychoanalyst and Organisational Consultant. As consultant to the United Nations and other organisations, he has been working with refugees, tortured persons and other survivors of political violence and disasters in many countries. He offers specialist training and organisational consultancy internationally, and his writings have appeared in fifteen languages. Recently, he has been given Awards by the European Family Therapy Association for Life-time ‘Outstanding contribution to the field of Family Therapy and Systemic Practice’, by the University of Essex for the best ‘International Research Impact’, and by two Mexican Foundations for his ‘exceptional work with vulnerable children and families in Mexico’.

Dr. George Diakonikolaou

George Diakonikolaou is the Managing Director of “Project Management Coach” LTD, delivering services to business clients in the fields of Project Management, Leadership, Coaching and Organisational Development. His clients include companies such as Cosmote, Romtelecom, Vestas, ENEL, EDF etc. George is a visiting Faculty, teaching Project Management in the International MBA in Athens and Brunel Business School, MBA in London as well as Bradford Business School. He has received his First Degree in Electrical Engineering and Computer Science in National Technical University of Athens and his M.Sc. and Ph.D. in Computer Science from University of Manchester Institute of Science and Technology. George is the co-founder of the Greek Chapter of the Project Management Institute, a Certified Project Management Professional and a founding member of the Hellenic Coaching Association. He is also an NLP Trainer and Master Practitioner of NLP & Time Line Therapy®, a Master Practitioner of Hypnosis and an NLP Master Coach.

Currently, George is experimenting with the integration of Coaching, Organisational Development and Project Management in a field that he likes to refer as “Project Coaching”, an integrated model that achieves groundbreaking results in Strategic Projects, Programs & Portfolios, and executive teams’ performance.

George is a 2010 Diploma Alumnus.

Ana Rhodes Castro

Ana is an organisational consultant, trainer, supervisor and executive coach. For the last 10 years, she has worked as a trainer and facilitator with individuals and groups in diverse settings ranging from the Findhorn Eco village in Scotland, UK, Italy and Spain to Universities in Latin America, where she has taught conflict facilitation, leadership skills and peace studies.

She has trained in a variety of personal and organizational development skills including Appreciative Inquiry, Conflict Facilitation, Applied skills for sustainable social and culture change, Leadership and confidence building, Outcome Mapping, Supervision and Executive Coaching. She is now in the process of completing he Process Orientated Psychology Diploma.

From 2009 to 2013, she worked for the Findhorn Foundation, as HR Manager and then (2009) as CEO. During this time she also run her own consultancy business “Inspired Action” working with different client groups including cross-cultural education. She facilitates groups of up to 300 people in processes of socio cultural and organisational change, using tools that support diversity and deep democracy.
She deeply believes in cross sector engagement so she works with the corporate world, civic society and NGOs.

One of her greatest passions involves maximizing the inherent potential of individuals, groups and organisations in a way that is supportive and enhances natural leadership.

Tereza Venetsanou

Organisational Development and Business Transformation Consultant, Executive Coach and NLP Master Practitioner. Originally from a marketing background, Tereza has held leadership positions in multinational corporations such as Microsoft, Vodafone Global Enterprises and Wind. Currently, she is leveraging her corporate experience paired with coaching skills to consult and advise senior business leaders in the creation of state-of-the-art business models and solutions. Whilst supporting Impact through a combination of business development, training and coaching expertise, she is also supporting Vodafone Partner Services as a Sales Transformation Consultant.

Her focus has always been to drive and accelerate sales and business performance through people. She is as competent in generating marketing plans and supporting strategic priorities as she is in coaching senior leaders and building strong teams. During her career, she won numerous awards for extraordinary achievements and has a track record for successfully implementing transformational initiatives both at Vodafone Global Enterprises and at Microsoft. Her vision is to empower teams and individuals to reach their full potential within their business context.

She is a mother of two, devoted in personal development, constant learning and travelling.

Tereza is a 2019 Diploma alumna.

Suzanne Ferreira

Suz is a Physiotherapist (BPhysT – Cum Laude), a Pilates Instructor (APPI), an Acupuncturist (ACCP), a Movement Specialist, a Business Coach (IMPACT & Gestalt), a Sports Massage Therapist and the Founder of SFStudioslondon.
She has worked with patients and clients over the last 20 years including 13 years in her own practice. She initially qualified as a Physiotherapist in South Africa and has ever since expanded her career (knowledge, application and dedication) in the UK and Europe.
She is whole-heartedly devoted to improving people’s overall health and well-being; thus the wide ranging studies and experience set out above. Suz bucks the modern trend of (over) specialisation, and believes in a holistic approach to well-being. She believes that our three systems (mental, physical and emotional/spiritual) all play a fundamental role in how we live our daily lives and works with people across all sectors, individuals and groups, to promote well being and anchoring.
She loves the combination of hands-on therapy, talk therapy (coaching), and movement therapy to help heal her clients and to help them to perform optimally.
Suz has an outgoing, dynamic personality, she is passionate about nature, art, culture and absolutely loves sport, both as a spectator and as a performer. She has a natural talent to connect with people and make them feel comfortable and favours a direct and honest approach.
She leads SFStudios in London, runs retreats in France and has scheduled retreats in Greece for 2020. She works with clients world-wide and still has a very close connection to her roots, South Africa.

Suz is a 2016 Diploma alumna.

Diploma Testimonials 2019-2020

A life changing experience that gives you the knowledge to take the most important steps towards a better self and help others do the same. Simply priceless.
George Trichias

A great starting point on the (self) exploration of dealing with people. Bring your mental scuba gear along, you’ll need it.
Angelos Skembris, Castalia Technologies

A unique transformational and life changing experience emerged for me from absolute ‘synchronicity’! A great journey to awareness. A top-class and exceptional course, and absolute must for anyone who wishes to invest, looking for personal and professional development. A high demanding course in a challenging and demanding environment, which takes you out of your comfort zone. The course changed the way I see myself and the world around me.
Great environment, excellent Tutors. It is highly recommended.
George Papadimitriou, PM-Partners

It was the best investment I have ever made due to the insights and knowledge I got efficiently. The course was incredibly comprehensive and supportive of discovering ourselves and shadow.
The participants are carefully selected and through the exercises gave us the chance to understand, very well, personalities different from us. It was the first time that I felt what a team is.
If you are willing to ask yourself tough introspective questions and be prepared to put the work needed,
If coaching is something that interests you, this course is the right one.
It can equip you with all the tools needed to support and challenge your coachees to enhance their impact on work and life.
Michalis Maimaris, Knowledge TraininG & Consulting Ltd

The course coincided with a fundamental change in personal mindsets and external circumstances. The content and the processes in each session went beyond providing a coaching toolkit; they provided fuel for radical rethinking.
Michael Alexandratos, McKinsey & Company

The words coming to my mind when thinking of this Diploma: Interaction, insight, presence, revelation, authenticity, transformation, experience, team work, journey, vision, friends, excellence. Reaching a state of being. It’s all about leadership. Don’t miss this.
Apostolos Palaskas, Door Training & Consulting

The light is better here!
This course offers a huge potential for personal and organisational development. If you would like to extend your senses, awareness and embrace your motive as a leader, parent, citizen, human being don’t miss this unimaginable experience. With this course you will be able to clearly see, transmute, envision and take action.
Kostantinos Panoulas, Boussias Communications

A powerful journey for self improvement and self awareness. I highly recommend it.
Vera Pagkoulaki, ELVAL S.A.

The experience from attending the Diploma seemed like being in a room full of doors leading to brilliant material. It converges together disciplines as diverse as Business Psychology, Presence, Strategy. I emerged out of the Diploma much more self aware and intentionally able to influence my environment than before. Dare to take a dive and enjoy!
Thodoris Markopoulos, Evolut

A compressed experience of life that changed structural aspects of who I am. And brought more clarity on how to support myself and others to thrive.
Open yourself, your mind and your time for this valuable journey now
Sofia Katsara, Microsoft

Find the treasure: an exceptional journey towards fulfilment. The information, the interaction and the feedback from facilitators and participants aloke, quickly lead you into another dimension; and to a continuous strive to find yourself and overcome your boundaries.
Pantelis Boussias

I would say that this was an enlightening life experience. Strongly recommended for anyone wishes to change angles and eventually evolve!
Still becoming a Jedi needs time, effort and the mentality to transform yourself and others.
«Be the change you want to see in the world» Mahatma Gandhi
«Choose your battles» Vassilis Antonas
Ioannis Vriniotis, Microsoft

A transformational journey on Leadership, Executive Coaching and Organisational consultancy, that opened new horizons, boosting my professional and personal evolution.
Yanna Andronopoulou

I went into a journey deep into myself. With me were inspiring Facilitators and supporting, exceptional Colleagues.
During this I have evolved in ways I couldn’t imagine or fathom.
I am still not back from this journey nor do I wish to. I will stay on it. Do join.
Penny Kapitsinou, Impact / Spiti

To view a full list of our testimonials click here


Our consultants have provided Executive Coaching, OD consulting, Corporate Counselling and Training to several clients in Greece and internationally from different industries and functions.
List of all clients….

Your Team

Vassilis Antonas
Vassilis AntonasFounder, Managing Director, Diploma Director
George Diakonikolaou
George DiakonikolaouAssociate
Tereza Venetsanou
Tereza VenetsanouAssociate

Contact Us

39, Ch. Trikoupi Street
Kefalari, Kifissia
145 62 Athens, Greece
Tel: +30 210 8014505