Here you will see all the Success-Stories of our students. This is the Dia Gerontoudi Prep Center Hall of Fame, which features alumni from all of the world’s top universities. This is no coincidence, as we are the only boutique postgraduate preparation centre in Greece. In our centre we dedicate to each and every one of you the time that he/she deserves. You are all important which is reflected in our successes. On the map you will see the over 230 universities around the world where our students have studied or are studying and some of their most important stories!


Vasilis Karkantzos

MBA, Harvard Business School (’18) / McKinsey&Company, Business Analyst / Civil Eng. NTUA / Athens College (HAEF) / GMAT 760, TOEFL 117, GRE 170/161

During my preparation for an MBA in the USA, I worked closely with both Dia Gerontoudi and Thomas Kalandranis. For her part, Dia was much more than a great teacher. She was a real mentor! Her perfectly organized method (class courses and labs) enabled me to identify my weaknesses and improve on them, in order to excel at the GRE/GMAT and TOEFL exams.

Michalis Frouzis

MBA 20′, Harvard Business School / NTUA Diploma in Electr. Engineering / GMAT 770, IR 8/8

Applying for graduate programs is undoubtedly a draining process and the importance of having the right allies along the way simply cannot be overstated. For me, the right allies were Dia Gerontoudi and Thomas Kalandranis.

Anna-Lali Tsilidou

ΜBA 21′ Columbia University / Mc Kinsey Bus. Analyst / BSc in Accounting and Finance, UOM / GMAT 750

Having worked with Dia Gerontoudi and Thomas Kalandranis before on the GRE exam and on M.Sc. admissions, Dia Gerontoudi Prep Center was the obvious choice when I started thinking of GMAT and applications to MBA programs.

Thodoris Margiolas

Five years after my rewarding experience at Dia Gerontoudi Prep Center, I have embarked on my journey at Harvard Business School. As I look back, I am profoundly grateful for the pivotal role that both Dia and Mr. Karalis played. They did more than prepare me for the GMAT; they laid a strong foundation for an ongoing pursuit of excellence.

Maria Paziotopoulou

Harvard Law School, LL.M. (Class of 2024) / Trainee Lawyer at A.Papapanagiotou IP & IT Law Firm / Co-Founder & Executive Director The Law Project / LL.M. – LL.B. (Hons) NKUA / TOEFL 111 / IELTS 8

Applying for a Master’s degree to some of the most prestigious universities in the world is truly a life-changing decision. I realized that the key to achieving my goal would be selecting a team with a high level of professionalism and a strong work ethic.

Thanasis Basiakos

My admission to Georgetown University became possible thanks to the invaluable assistance provided by Mr. Thomas Kalandranis and the Dia Gerontoudi Prep Center.

Simon Sakellaris

Dia Gerontoudi Prep Center played a pivotal role in my successful application process for the Masters in Financial Analysis (MFA) program at London Business School…I am immensely grateful for his mentorship, and I have no doubt that his expertise and dedication will continue to empower the journeys of many aspiring candidates.

Philippos Nakas

MS in Symbolic Systems, Stanford University / BA Mathematics and Philoshophy, Yale University / GRE Q169/V169

The instruction I received by Mrs. Gerontoudi throughout my preparation for the verbal and written section of the test was consistently insightful, highly personalized, and, most importantly, to the point.

Stathis Iliakis

Ph.D. in Chemical Engineering, MIT / Diploma in Chemical Engineering, NTUA / TOEFL 104

Applying to the Ph.D. program at the most prestigious engineering universities in the world is definitely a stressful and tough task as they demand a nearly perfect score on TOEFL and an exceptional personal statement.

Christos Doukas

MBA 25′, MIT, Sloan School of Management / BSc in Economics, AUTH, Military School of Combat Support Officers / GMAT 720

I contacted Dia Gerontoudi Prep Center on the strong suggestion of a good friend, intent of aiming for a top MBA program in the USA. Honestly, I was a little concerned about whether the scale of my ambitions and dreams was in fact too much for my abilities.

Feli Oikonomopoulou

MBA, Yale SOM ’24, Dean’s Scholar / VP at Bank of America, London / LLM Oxford / LLB NKUA / GMAT 730

When I first considered applying to MBA programs, I could not imagine how challenging this process could be. Attending classes with Dia Gerontoudi Prep Center armed me with the knowledge and confidence to achieve a high score in the GMAT exam and be admitted to top universities, including Yale SOM, which I finally attended on a merit-based scholarship.

Alex Angelopoulos

Harvard MBA ’24 / Diploma in Mechanical Engineering, NTUA / GMAT 740

Yet after a few months alongside her guidance, I managed to score 40 (91st percentile) which boosted my overall performance significantly alongside my Quant score.

Menelaos Alexandrakis

MPP, Harvard Kennedy School / BSc in Business Administration, Fordham University

When I started taking courses for the GRE at the Dia Gerontoudi Prep Center, I was quite stressed out. Memories of last-minute undergraduate applications flashed back; I wanted things to go differently this time. Thanks to Dia and her team, they did.

Ilias Eliezer

Master of Financial Engineering MFE, Anderson School of Management, UCLA / BA in Economics, Math, University of Maryland / HAEF / GMAT 760

When I returned to Greece in the summer of 2021 to serve in the military, I felt overwhelmed. This sense of dysphoria, accompanied by the fact of not knowing what to expect from the GMAT exam, for which I was planning to study while doing my military service, eroded my confidence.

Vassilis Koutsoumpas

Georgetown University, MPP (‘24) / City of Athens, Policy Advisor / Co-Founder-Executive Director WeFor / LLB-LLM DuTh / 2nd General High School of Livadia

As one scrolls down this list, one can’t help but be impressed by the success stories of young people from all over Greece. Their journey towards their goal has been an accumulation of hard work, discipline, and a compelling narrative that made them stand out. I am filled with joy and humility to be included among them.

Vasilis Mantzios

Harvard MBA 23′ / MEng in Chemical Engineering, University of Bath / GMAT 700

When I decided to pursue an MBA, I knew that everything starts with the GMAT. Working with Dia for my GMAT was absolutely the right decision and I have only positive things to say about her methodical working methods.

Dimitris Frouzis

Columbia MBA 23′ / Business Analyst, Mc Kinsey & Co / BSc in Management, Science and Technology, AUEB

In such exhausting journeys, as the one of MBA applications, especially when combined with demanding occupation, selecting the right ‘team’ around you is pivotal to success. The importance of great GMAT tutoring is incredibly valuable (one can definitely find it at this center), but Dia Gerontoudi Prep Center is much more than that.

Maria Stavridou

MPH, Global Health, Harvard T.H. Chan School of Public Health / Economic Advisor at Department of Health and Social Care, UK gov. / MSc in Economics, University of Warwick / AUEB Economics

Contacting Dia Gerontoudi Prep Center was one of the first things I did when I started thinking about applying for a Master of Public Health (MPH) program at top universities including Harvard, Hopkins, Columbia, Yale, etc. Having worked with Dia and Thomas 8 years ago on the GRE and IELTS exams and my MSc admissions…

Maripeny Kouskouki

MSc in Orthodontics and Dentofacial Orthopedics, Eastman Institute for Oral Health, University of Rochester, NY / NKUA Dental School

In order to achieve my goal, I needed the appropriate guidance and preparation. The professionalism of the experienced team of Dia Gerontoudi Prep Center was my best teammate throughout the application process.

Giannis Froussos

LBS MBA 24′ / MEng in Civil Engineering NTUA / HAEF

Ever since I set my eyes on an MBA degree from the London Business School, I knew it wouldn’t be an easy task. As such, I needed the best guidance and preparation possible, and that is what I ultimately found at Dia Gerontoudi Prep Center.

Simos Galatis

MFA 23′, London Business School / BSc in Accounting and Finance, AUEB

Pursuing a master’s degree in Finance, I knew that the GMAT exam was an integral part of the application process. Choosing to prepare at Dia Gerontoudi Prep Center played a crucial role in the success of my applications; I will never forget the day I received an offer from London Business School for the Masters in Financial Analysis Programme.

Spyros Tsaousis

MiM, London Business School / BSc in Economics, AUEB / GMAT 710

A solid GMAT score and well-constructed essays were key to achieving my academic aspirations. It was a privilege to tackle this rewarding journey alongside the team at the Dia Gerontoudi Prep Center.

Nick Karouzakis

MEng in Civil Engineering, NTUA / MSc in Management of Information Systems and Digital Innovation , LSE

Ever since I can remember, my ambition was to pursue my master’s degree at London School of Economics and Political Science. To succeed, I knew that I would need the appropriate guidance. I needed someone who would be able to understand my vision and help me translate it into a powerful personal statement.

Achilleas Valozos

Master of Management, UBC Sauder School of Business / BSc in Mathematics, Aristotle University of Thessaloniki

When I decided to apply for the Master of Management at UBC Sauder School of Business I knew that choosing a team distinguished by its professionalism and strong work ethic to assist me with both the GMAT test and the application process would be the key factor that would help me achieve my goal.

Spyros Terlemes

BSc in Math and Physics, Princeton University, Scholarship

Receiving the acceptance decisions from Princeton and Yale was really one of the happiest moments of my life. It was a success moment that beyond my family and school, I owe it to Dia Gerontoudi Prep Center! During my SAT preparation process, I had the opportunity to be taught by an amazing teacher, Dia Gerontoudi…

Fanis Papanikolaou

MSc in Financial Data Science, University College Dublin Smurfit Business School / BSc Banking and Finance, Piraeus University

Dia Gerontoudi Prep Center is the obvious choice for anyone looking to further their studies. More so if you need guidance and are unsure about what and where you want to study. The entire team consists of absolute professionals, who know the “market” more than anyone.

Stella Roussou

LL.M in IP & Technology Law, IE Law School, Madrid / Trainee Lawyer at A.Papapanagiotou IP & IT Law Firm / LL.B NKUA / Vice President in charge of Marketing – ELSA Athens

The entire team at the Dia Gerontoudi Prep Center” is equipped with the appropriate knowledge and experience to guide you and help you achieve your academic goals. Mrs. Dia, with her knowledge and determination, manages to integrate you smoothly into the demanding GMAT preparation, while Mr. Kalandranis…

Maria Nefeli Bernitsa

MBA INSEAD ‘22 / LLB UCL / Senior Associate at Silver Circle law firm, London / GMAT 710

Working with the Dia Gerontoudi Prep Center was the single most important decision in my MBA journey and the key to getting into my school of choice.

Aliki Lavda

Master in Management, HEC Paris / Diploma in Chemical Engineering / GMAT 730

During my preparation for a Master’s Degree, one of the challenges that I had to face was how to accurately present myself and my achievements in my personal statement.

George Sarantis

Hellenic Dairies S.A. / London Business School MBA 23′ / BSc in Business Administration, AUEB / GMAT 690 / IELTS 8

Every MBA journey starts with the GMAT exam. This is not optional, this is mandatory. However, it is up to you to choose the right people to walk you through the path of success.