Our learning methods

The methods we use are based on proven creative and dynamic learning techniques that enhance reflection and make you aware of your possibilities for improvement. Our sessions are interactive, we make use of quizzes, games, physical dynamics, videos, discussions.

You will be able to apply the new insights and tools immediately after the training, as we work with your examples and situations.

Long-term results

Once the training is complete, we offer support and advice through practical coaching to ensure the changes take root and give you long-term effects.

Infographic on how Focus, Enthusiasm, Exchanging Ideas, and Commitment lead to Sustainable Results.

We are committed to your success and are only satisfied when we have reached your intended results.

Marianne Slotboom in Time Management training.Koos Vos in roll-play activity


The color yellow

Yellow represents light and energy, enhances original thinking and inspires change. It’s the color of communication, new ideas and optimism. In the vast majority of cultures around the world, yellow represents warmth and happiness. We are inspired by the virtues of the color yellow and keep these attributes at the center of everything we do.

Our vision

We aim to be place in Barcelona when it comes to creating inspiring leaders and high-performing teams within tech companies. You can count on the latest insights, methodologies and tools in our programs to make your teamwork constructive, creative and fun.

Our mission

We are a strategic partner and a practical developer of human behavior that helps you, your team and your organization to be more focused and effective. We will help you to make your workplace an inspiring place to be. 

Do you wish your organization had a more inclusive and engaging culture? If so, then let us put some Yellow in your world.

  • Positive collaboration via shared ideas
  • Creation of new solutions
  • Harnessing all kinds of diversity
  • Constructive feedback
  • Strong focus and priority setting
  • Transparent communication
  • Alignment in values and roles
  • Valid contributions of all team members
  • ‍‍Flexibility for change
  • ‍Enthusiasm and joy at work

Our values

Our values sum up who we are, how we work, and what makes us special.

Commitment to being experts in our field

We live on the bleeding-edge of the latest insights about neuroscience, leadership and teamwork, always improving our programs, and giving you the best practices available.

Making a difference that lasts

During our programs we have concern for the practical applications in daily work and we use strategies that secure sustainable results.


We listen & learn from our clients, adapt to their needs and adjust our programs based on what’s happening around us.


We take our cues from the sunny side of life. Our programs are inspirational and open, with an emphasis on fostering positive relationships. We are enthusiastic and optimistic about what we can do for our clients.

Let us put some Yellow in your world!
Marianne Slotboom assisting participants of Time Management TrainingPersonal learning guide - Time managementMarianne Slotboom giving feedback to participants of Time Management Training
Yellow, time management training with Koos Vos.


Even in a world full of disruptive technologies and innovation, in the end, it all comes down to people and teamwork. That’s our expertise! With our extended experience and our passion to create inspiring workplaces, we are highly equipped to help you build high-performing teams and develop into an inspirational leader.  

We make your teamwork work!

Meet our professionals

Marianne Slotboom, founder of Yellow

Marianne Slotboom, Founder

International Teams & Inclusive Leadership

In 2015, Marianne founded Yellow with the aim to contribute to the challenge within tech companies where highly talented employees, innovators, and critical thinkers need to work together to create great products and services.
Her passion is to develop innovative, self-organizing teams and happier organizations.

More about MarianneTwitterLinkedin

Marianne is licensed in Social and Organizational Psychology and holds a postgraduate degree in Organizational Strategy from the Erasmus University, the Netherlands.

She is certified in methodologies like HBDI, NLP, the case study methodology, transformational coaching, and problem analysis strategies.

As a trainer and coach with a background in management consulting, she is experienced in working in stressful environments and companies that span locations and cultures.

Born in Rotterdam, Marianne first came to Barcelona in 1998, chasing her dream to live in an exciting Mediterranean metropolis.

Yellow’s excellence lies in the strength of its team, experienced and qualified professionals with a plethora of international clients, all successful in their respective fields.

Koos Vos, team member of Yellow

Jacobus "Koos" Vos

Neuroleadership & Communication

Koos is a consultant, international trainer and speaker, accredited user of LIFO and DISC, member of the AECOP Coaching Association. In 2013 he completed the Master Executive & Organizational Coaching at EADA Business School Barcelona.

More about Koos

He has over 20 years of experience in training and coaching for executives and entrepreneurs and is the developer of the physical coaching model TRIP, together with movement artist Helena Lizari.

Koos studied Psychology at the University of Amsterdam, after which he also followed a professional acting training. The combination of his academic and artistic backgrounds forms the base of a personal, playful and practical approach.

Born in The Netherlands, he moved to Spain at the age of 35, following his Spanish wife back to her roots. Since then he has lived more than 15 years abroad in which period his daughter Nora was born.

Gabby Maguire, team member of Yellow

Gabby Maguire

Team Development & Communication

Gabby has a degree in History and English, and she holds Masters in both Teaching English to Adults and Integral Psychotherapy.
She is certified in Extended DISC coaching and trained in ORSC (Organizational and Relationships Systems Coaching) and she is currently studying to gain the ICF Diploma.

Gabby’s background in Education as Train the Trainer, Team Leader, Speaker at international conferences and Writer have provided her with a broad skill set that she effectively employs to support cutting edge teams in the business world. She specializes in enabling teams and individuals to overcome conflict and adapt to change.

Gabby is passionate about creating dynamic, interactive workshops designed to develop empathy, psychological safety, and excellent communication skills in the workplace!

She has collaborated with multinational companies such as Typeform, King, ADP, Wallapop and Servihabitat.

Gabby was born in Ireland but moved to Barcelona over 25 years ago,
escaping the windswept rainy climate of the West of Ireland! She has been captivated ever since by the diverse landscape and pleasant climate all over Catalonia, and that, combined with the excellent cuisine and vibrant culture, means that Barcelona is now her home!

Jose Powell, team member of Yellow

Jose Powell

International Team Development & Leadership

Jose is a corporate trainer and facilitator, as well as an executive coach. She has extensive experience working on leadership, D&I and creating inclusive company cultures, emotional intelligence programs and programs for team development.

She is a certified ICF (InternationalCoach Federation) coach, ORSC (Organizational and Relationships SystemsCoaching) team coach, NLP Practitioner, trained as DISC Analyst. She also has training in somatic coaching and uses embodied practices to support self-awareness and transformation.

Jose has worked with multinational companies like Salesforce, King, Allianz, Ubisoft. She also collaborates with leading learning and development centers such as Universitas Telefonica, AEABusiness School and UNIR.

Previously Jose has more than 12 years experience in management roles, focusing on team building, training communication skills, sales and negotiation techniques, as well as networking and influencing skills. She has worked with multicultural teams all over the world, adapting to different cultural norms, business and management styles.

Jose is British born, lives in Barcelona and works in both English and Spanish.

Jose Powell, team member of Yellow

Kitty van Dijk

Change Management & Performance Management

Kitty works as Consultant, Trainer, and Coach, helping people & organizations optimize performance and wellbeing. She holds a Master´s degree in Business Administration (MScBA) in Management of Change, obtained at the Erasmus University Rotterdam School of Management, The Netherlands. She is a CTI (Coaches Training Institute accredited by ICF International Coaching Federation) trained Co-Active Coach.

After obtaining her Master in Business Administration (MScBA) in Change Management, Kitty started her career as strategic HR Business Consultant. Designing & delivering HR projects related with organizational design & organizational culture, compensation & benefits, competency management and performance evaluation.

She moved to Barcelona, Spain in 2009, where she since then obtained broad working experience in international companies such as Hewlett Packard, ADP, and smaller fast-growing companies. With her versatile profile and hands-on attitude, she worked in a variety of roles such as HR Manager, Partner Management & Project Management.

Especially passionate about the human, personal element of Change Management, she finalized her Co-Active Coach Training in 2021. Kitty is on a mission to make work more meaningful & fulfilling, aligning people´s individual purpose, goals and skills with organizational goals and purpose, optimizing both well-being and performance.Originally from The Netherlands, Kitty speaks English, Spanish and Dutch.