A Unique Team With A Unique Vision

Synthesis offers safe, legal, medically supervised psychedelic retreats in Amsterdam. We make the psychedelic experience accessible for curious individuals who want to utilize moderate-to-high doses of psilocybin truffles to catalyze creative breakthroughs, explore consciousness, find meaning, improve confidence, and search for a mystical experience. Find out here what our customers say about us.


Synthesis spearheads a new era in the integration of psychedelics into modern culture. In professionally curated settings, these remarkable molecules can be agents of transformational experiences. Psychedelics have the potential to restore our sense of wonder and foster a renewed sense of connection; to ourselves, others, and the natural beauty of the wider world.
“Our name is a tribute to our core mission; providing an integrative approach to transformative wellness synthesizing modern science and medicine with wisdom traditions, ancient shamanistic rituals, and spiritual practices.”
Through workshops and ceremony, open-dialogue, bodywork, meditation, sound and psychedelic education, led by our professional facilitators, psychedelic experiences have the power to restructure thoughts, sharpen perceptual lenses, and awaken expanded forms of consciousness. This sense of possibility is what you will discover at Synthesis; a locus for profound transformation.
Lead Retreat Team

Natasja Pelgrom

Spiritual Care | Lead Facilitator

Throughout her professional development, Natasja maintained strong ties to her innate sense of spirituality, by concurrently studying energy healing, Reiki, ThetaHealing®, emotional freedom techniques (EFT), neuro-linguistic programming (NLP), and till today receiving sacred teachings from Native American and North European Shamanistic lineages.

She is a highly intuitive guide and has trained, assisted and facilitated in 500+ psychedelic ceremonies. As a medicine woman operating internationally, she curates medicine retreats, teaches empowerment workshops and developed a psychedelic integration and Self-Love program.

Daan Keiman

Daan Keiman

M.A. Spiritual Care | Lead Facilitator

Daan holds an MA in Spiritual Care and previously worked for the renowned mental health care and addiction research institute, the Trimbos-institute. His experience with guiding and caring for people in altered states of consciousness spans over a decade.

He draws from his personal contemplative practices, psychedelic research and his professional experiences to create compassionate and powerful containers for personal transformation. As an avid explorer of consciousness, he is highly capable of guiding others through the landscapes of the mind.

James Clifton

James Clifton

Integral Psychotherapist & Counsellor | Lead Facilitator

For more than 3 decades James has studied many of the world's perennial philosophies and engaged fully in a number of the great wisdom traditions, with specific interest in non-ordinary states of consciousness.

Trained formally in transpersonal psychotherapy and integral coaching and working with trauma and addiction, he is experienced at tracking tension and points of change and growth in individuals and groups. This unique experience allows him to fully understand the role of psychedelics and entheogen’s as a catalyst for authentic transformation.

Co-Lead Retreat Team
Tessa Van De Ven

Tessa Van De Ven

Co-Lead Facilitator

In her role as co-lead facilitator, Tessa takes individuals on introspective journeys to connect with their true authentic self. Psychedelics entered her world when she experienced a challenging identity crisis and sought out nature-based healing modalities.

This exploration of self-healing led her towards various traditional and modern psychedelic ceremonies working with skilled guides and studies in the transformative potential of natural compounds. Tessa's strong intuitive abilities, empathy skills and deep connection with psychoactive plants make her an excellent guide on your journey through expanded states of consciousness.

Lorraine Glatigny

Lorraine Glatigny

Co-Lead Facilitator

This Western healer began her work with Shipibo traditional medicine in 2008. During a one year initiation she learned techniques from a variety of expert healers, where she performed several diets and long stays in the Amazon rainforest. She also spent several months with various traditional Filipino healers who passed on ancient practices of healing, such as the "Hilot" therapeutic massage. From there, she went to meet the Queeros, the last Peruvian Andes descend from the Incas and lived among the Tao't Batu (people of the rock) in the Philippines.

Sven Kimenai

Sven Kimenai

BSc. Psychobiology | Co-Lead Facilitator & Breathwork Coach

Sven has a background in Psychobiology & Supplement Development. After his studies, he went on a path of exploring science-based methods for self-healing. He became a Wim Hof Method Instructor, a Breathwork Facilitator and started studying Psychedelics for transformational healing.

He emphatically empowers others to step out of their comfort zones and supports them in exploring their inner landscapes. His aim is to research and apply psychedelics and breathwork, to catalyze personal growth, insight & human connection.


Tatiana Santini

PhDc. | Co-Lead Facilitator

Tatiana has been formally trained at a post graduate level in Psychedelic-Assisted Therapies and Research from California Institute for Integral Studies (CIIS). She holds an MA in Counseling and Psychotherapy from Adler Graduate School, and she has been working as a psychotherapist, clinical mental health counselor, trauma therapist, and substance use counselor for over a decade now.

She has also been formally trained in Spiritual Psychotherapy, Somatic Experiencing, EMDR, DBT, Mindfulness Based Cognitive Therapy, Mindful Self-Compassion, and Ketamine Assisted Psychotherapy.



BSc. Psychology | Co-Lead Facilitator

Roos-Veerle is a Psychologist and Yoga teacher. She facilitates Life-Coaching (Acceptance and commitment therapy), workshops and retreats in the field of physical, emotional, mental and spiritual wellbeing.

Since she was little she has been fascinated by what makes people happy and healthy. Traveling around the world for 2,5 years, meeting people who have had radical remissions, studied and worked with medicines coming unrefined from nature, gave her many insights.

Assistant Retreat Team
Marta Kaczmarczyk

Marta Kaczmarczyk

MSc Cognitive Science | Retreat Assistant

Marta is a cognitive scientist (MSc) who has been exploring the concept of the mind from the perspective of science but also Jungian psychology, mindfulness, and somatic therapy.

She co-founded a non-profit psychedelic-oriented community platform and has been giving lectures on psychedelics, focusing on informed use and harm reduction.

Additionally, Marta is a biohacking consultant and a psilocybin truffles guide. In both of these activities, she supports people with the opening to the message of emotions and feelings, to find a fuller life.

Dorien Nagler

Dorien Nagler

Retreat Assistant & Breathwork Coach

Dorien is a woman of breathwork. With this powerful tool, she helps people to connect to their inner being and guides them to the place where they feel at home with themselves. For as long as she can remember, she had this sense of wanting to know what it means to be truly alive.

When she stumbled upon breathwork, she knew she had found something special. Breathwork gave her a new perspective on life and made her understand herself on a profound level. Through the expansion of breath and body, she guide others towards their full potential.


Odin Pepper

Retreat Assistant

Odin is a Dutch-American, born and bred in Amsterdam. For the past decade, he has worked as a cinematographer after earning his Bachelor of Arts degree at the Dutch Film Academy.

For the past few years, he has been on a path of self-exploration, self-development, healing, and trauma processing. He has been exploring different modalities and methods like tai-chi, reiki, the healing properties of psychedelics like ayahuasca and psilocybin containing truffles, meditation and different forms of movement therapy. He's recently completed a 2-year intensive course as a certified AuraTouch practitioner.


Hanneke Meesters

Retreat Assistant

Hanneke began working with psychedelics in 2012. She discovered the therapeutic work of plant medicine in combination with ceremonial practices after spending time in the Guatemalan jungle where she studied the Mayan culture, herbal medicine, and Shamanism. After this beautiful and intense experience, Hanneke decided to combine her own intuitive skills with psychedelics and lifestyle coaching. Since then she has been working with individuals and groups as a coach and retreat facilitator using plant medicines, bodywork, and mindfulness practices to nurture alignment and synchronization.


Jeff Hamburg

Retreat Assistant

Jeff’s arrival in the healing space occurred last decade when suddenly hypnotherapy, Holotropic Breathwork, psychedelics and Itzhak Beery, his shamanic teacher, almost simultaneously entered his life.
Jeff is a classical composer as well which has often taken him via his music into the inner world. By combining all of these modalities, he has developed an uncanny skill of navigating these inner worlds as well as creating a safe space for others to explore their own inner dimensions.


John Newton

Retreat Assistant

John has widely studied the field of Transpersonal psychology and philosophy, and has a passionate interest in psychedelics, meditation and awakening. 
He has worked in clinical research with psychedelics, harm reduction services, and has a wealth of experience in providing psychological care, especially in supporting those undergoing challenging psychedelic experiences.   
Formally trained as a mindfulness coach, John is a long term meditation practitioner, and is deeply committed to supporting personal insight in service of collective transformation.
Venue Team

Lotte Van Cleef

Head Chef

Lotte had completed the VIP Health & Nutrition training. Pure and tasty cooking is her passion.
She gives you the experience that a healthy and vegetarian meal can be very delicious. While cooking she loves to share her knowledge and inspiration about good nutrition for at home.


Maria Petit

Venue Manager

Former Motorola Ltd Commercial Director Europe Middle East and Africa. Maria left the corporate world in 2009 on a two year sabbatical which led her to study Arabic in Yemen, play polo in Argentina and launch her first start-up JAM Language. During the decade that followed, Maria lived in United Arab Emirates, Mexico, Jordan, Yemen, Spain, Argentina and Brazil where she co-founded the events company SPNM.

Afterwards she detached from all material belongings other than two suitcases as a digital nomad living between Europe and South Africa for four years chasing the summer. This period led her down a road of self discovery which included living in Osho meditation communities in Germany and in Uruguay, attending Humaniversity and getting certified as a Human Potential Coach.

Medical & Psychological Support Team

Emily Kulpa

Pharm.D. | Director of Medical Screening

Emily is a licensed clinical pharmacist with a background in medication therapy management. She is highly experienced in conducting comprehensive medication reviews and medication reconciliations focusing on optimizing therapeutic outcomes.

She received a B.S. degree in Biology from the University of Wisconsin and earned a Doctor of Pharmacy degree from Concordia University Wisconsin. She is passionate about health, wellness, and the healing potential of psychedelics. Currently, she is involved in microdosing research at the University of Toronto Center for Psychedelic Studies by serving as head pharmacist.


David de Wied

MSc. Clinical Psychology | Medical Screener

David graduated from Utrecht University in the fields of Clinical Psychology and Cognitive Neuroscience. His research has been focused on set and setting factors such as the role of music and the effects of different social and physical contexts on the psychedelic experience, a collaborative project with Imperial College and the Psychedelic Survey.

At Synthesis he performs exploration calls and is a member of the medical screening team, utilizing his clinical expertise in helping determine if people should come attend the retreat. David is particularly fascinated by visionary experiences and cognitive changes from psychedelic experiences, as well as finding the right therapeutic approach to work alongside these medicines.


Dr. Tim Read

MD. FRCPsych. | Lead Supervision & Internal Training

Tim is a medical doctor, psychotherapist, and consultant psychiatrist in independent practice in London. He led the Crisis Intervention Service and the Psychiatric Liaison service for twenty years at the Royal London Hospital. He has held administrative posts such as Clinical Director and College Tutor, is a Fellow of the Royal College of Psychiatrists and member of the Psychiatry and Spirituality group. Tim holds degrees in neuroscience and in medicine, has completed training in psychoanalytic psychotherapy with the Institute of Group Analysis and transpersonal psychotherapy with Grof Transpersonal Training, and is additionally a qualified holotropic breathwork facilitator.

Corporate Team
Melissa Watkins

Melissa Watkins

Operations Manager

Melissa has a broad background in operations. Before joining Synthesis, she managed a luxury diving resort in the Philippines, supported a large scale IT implementation in a Dutch hospital, and earned her stripes as a project manager at an international marketing agency.

With over 10 years of personal experience working with psychedelics ceremonially, she’s bringing her process management and coordination skills to Synthesis.

While not oiling the wheels in our corporate office, or holding space during our retreats, Melissa is working towards her degree in Psychotherapy, specialising in embodiment, sexuality and psychedelic-assisted therapy.

Jakobien van der Weijden

Jakobien van der Weijden

Customer Service Manager

Jakobien is a Media Studies graduate and former marketer who has been in service of the psychedelic renaissance since 2003. She co-founded a microdosing information platform and has been part of several psychedelic research organisations in the Netherlands.

At Synthesis she supports our attendees on their pre and post retreat journey. When not connecting with you for your exploration call or running corporate operations, she is a Holistic Health Coach in training. She has a strong belief that through the therapeutic use of psychedelics we can activate our inner healing intelligence.



Operations Support Manager

Arin has a background in business, leadership development and yogic philosophy, and has spent most of her career as a startup Founder working on projects to scale healing and transformative experiences.

She is a Reiki Master Teacher, and is certified as an integrative psychosomatic coach with special concentration in relationships and sexuality. She believes business is a powerful vehicle for positive change and that change has to start at the heart of business: its people and it's leaders.

Her journey with Psychedelics began in Peru's Sacred Valley, and she is passionate about bringing more integration and balance to the healing journey through embodiment and self-care.



Financial Controller

Ethan is the financial controller at Synthesis. Over the past 15 years, he has worked in the private sector managing community-based projects for start-ups, state and federal government projects in the U.S. Ethan is especially passionate about conscious organizational strategy in the psychedelic space, financial modeling and providing data-driven insights to inform strategic, financial, and operational decision-making across the company.


Austin Piedmont

Digital Media Manager

Working for his first start-up while still in high school, Austin prides himself in his creativity and storytelling abilities. Being a hands-on learner, he taught himself skills such as web design, photography, videography, and graphic design - to name a few.

When he's not working, Austin spends his time with his wife and three children. His hobbies include ju jitsu, video games, and reading philosophy. He also volunteers at the organization he founded, The Collective Unconscious, which focuses on improving the psychological well-being and development of university students.


Jessica McCulloch

Content Marketing Specialist

Jess has worked in many marketing and writing positions in the arts, architecture, tech and luxury global FMCG brands over the last five years.

With a passion for the integration of science in the arts, Jess received a first-class honours degree and a writing award in History of Art, and earned a Masters in Design, Culture and Society. In her free time, she’s the Editor-in-Chief of a Bioart foundation called Unbore Collective, and loves exploring galleries and museums.

Jess is happy to work for a conscious startup that contributes to social good. She brings inspiring editorial about the science and stories of psychedelics to our curious audience.

Management Team


Co-Founder & Chief Visionary Officer

Martijn is the Co-Founder of HighExistence and Apotheosis, has a background in interdisciplinary science and philosophy, and with a strong foundation in coaching and entrepreneurship, he aims to make psychedelic tools accessible in a safe, legal, and modern context.

Martijn has been writing and speaking about psychedelics, interviewing experts in this field, and helped organize The Interdisciplinary Conference on Psychedelics Research 2016 in Amsterdam.

He first reached out to psychedelics when he was in search of new perspectives and clarity to reorient his way of being. Today it is his mission to lower the barrier for deep transformation.



Co-Founder & Director of Business Development

Myles has spent his career on three different continents launching or leading VC-funded startups with technological, socially responsible, and green initiatives.

He has a strong belief that business and capitalism, when incentivized correctly, can be the most powerful tools we have to make positive, sustainable change in our modern society, and is excited to bring his experience to the psychedelic movement.

Specifically with Synthesis, Myles looks forward to developing an impact-focused business model that increases access to safe, legal and professionally-guided psychedelic experiences and sets an example for what a psychedelic-integrated future can look like.



PhDc. | Chief Executive Officer

Rachel is a serial entrepreneur, conscious business and leadership coach, speaker, and conscious social change facilitator with nearly 20 years of experience working with clients across the U.S., Europe and East Africa.

In addition to her passion for conscious business and leadership, Rachel is focused on the transformation of trauma into action and leadership. Her practice includes a variety of modalities integrating body, breath, meditation, and creative arts-based practices.

Rachel holds a B.A. in Transformative Education & Leadership and a M.A. in Clinical Mental Health and Mindful-Trauma Informed Leadership. Rachel is currently working on her PhD in Integral/Transpersonal Psychology.

Advisory Board

Dr. Robin Carhart-Harris

Advisory Board Member

Robin is the Head of the Centre for Psychedelic Research, in the Department of Brain Sciences at Imperial College London, where he has designed a number of functional brain imaging studies with psilocybin (magic mushrooms), LSD, MDMA (ecstasy) and DMT (ayahuasca), plus clinical trials of psilocybin for treatment-resistant depression. His scientific contributions to psychedelic-assisted therapy could play a significant role in the future of psychedelics for mental health care.

Robin states that scientific investigation into the therapeutic potential of psychedelics is vital for combating the mental health crisis. As a partner with the center, scientific research shows that the Synthesis experience was found to significantly reduce symptoms of anxiety and depression, improve sense of wellbeing and emotional stability, and increase connection to self, others and nature. Legal, professionally-organised retreats like Synthesis can be a safe way for people to experience the transformational potential of psychedelics, and they can also be a great source of data for research, helping to further advance the field. Robin is excited to continue working alongside Synthesis to provide high-quality services and meaningful scientific research for the psychedelic community.


Dr. Rosalind Watts

Advisory Board Member

Rosalind is the Lead Clinical Psychologist at Imperial College London’s Centre for Psychedelic Research. Her clinical team has been pioneering research in the therapeutic potential of psilocybin, particularly for depression and disconnection.

Rosalind has developed a psychedelic therapy model ‘Accept, Connect, Embody’, and a psychometric measure of ‘connectedness’ which her qualitative research identified as a mechanism of therapeutic change in psychedelic approaches. Collecting data from our participants, her research has recognised consistently positive outcomes for people attending Synthesis retreats. Rosalind will use her expertise to optimise the Synthesis retreat model, continue scientific research and develop a clinical model to help more people with mental illnesses in the future.


Tero Isokauppila

Advisory Board Member

Tero is the CEO and Founder of Four Sigmatic, a global superfood company helping people to elevate their wellness with adaptogenic mushroom ingredients. He is also the author of two best-selling books Healing Mushrooms and Santa Sold Shrooms.

A respected expert in the industry, Tero speaks at various events and was chosen twice as one of the world’s Top 50 Food Activists. Tero believes that professional, legal and modern contexts like Synthesis are making psychedelic experiences more accessible to help people gain the benefits of greater connection, personal healing and meaningful insights from a single dose.


Join The Synthesis Team