Experience New Ways Of Being
A Legal, Professionally Guided Psychedelic Retreat Program
to Support Your Journey Towards Wholeness



Are You Curious About How Psychedelics Might Support You in Connecting to Your Authentic Self?

Join Us for this Cornerstone Experiential Program Designed to Reveal Your Potential for Personal Growth and Expansion.

Interest in psychedelics and the potential they hold to unlock latent parts of ourselves, kick-start behavioral changes, and address emotional, spiritual, and physical challenges has created an increasing demand for access.


With a proven track record for leading safe and legal psychedelic retreats for more than 2000 individuals, Synthesis has collected years of data, experience, and anecdotal success stories that make us uniquely qualified to offer you the opportunity to experience the potentially life-enhancing benefits of a psychedelic retreat experience.


Immersion Retreat—a comprehensive experience that includes pre-retreat preparation, a 5-day psychedelic-supported retreat, and post-retreat integration—is our cornerstone program designed for those who are eager to gain a deeper understanding of their true nature, tune in to their deepest wisdom and truth, and unlock their unique gifts and talents. 



This is a legal opportunity to take moderate to high doses of psilocybin that carefully creates a safe, intentional, and transformative container consisting of preparation and integration components essential to activating the full potential for personal breakthroughs. 


Past Immersion Retreat participants have reported their experience provided:

  • The ability to access deeper levels of consciousness promoted new insights and sparked creativity.
  • A deeper connection to others and the larger world encouraged the development of stronger personal relationships.
  • Increased resilience and a feeling of more balance and peace as they navigate life.
  • A greater sense of purpose and meaning in their life, resulting in a renewed sense of focus and direction.

Synthesis is committed to safely, legally, and effectively stewarding psychedelics into modern culture through our use of psilocybin mushrooms (or truffles containing psilocybin in the Netherlands). In our professionally curated settings, this remarkable organism can be an agent of life-enhancing experiences.


Using our integrative approach to transformative wellness, we combine leading-edge research with ancient wisdom traditions, rituals, and spiritual practices to curate a potent container that has the potential to catalyze change.


Led by professional facilitators, Immersion Retreat integrates psychedelic education, workshops, open-dialogue, breathwork meditation, sound, psychedelic ceremonies, and integration with the aim of restructuring disempowering thoughts, sharpening perceptual lenses, and awakening expanded forms of consciousness. 


The Retreat Team will support you by creating a safe container conducive to deep exploration. They have worked with Synthesis for years, leading ceremonies at the facilities in Costa Rica and The Netherlands. This diverse team possesses a range of holistic, therapeutic, and shamanic qualities. In addition, students from the Synthesis Institute Practitioner Training will join as assistants to provide support. They will aid with operational aspects of the retreat as well as serving as helpful allies on your journey.

What People Are Sharing About Their Immersion Retreat Experience

"This taught me to push my preconceptions aside and be very true, honest, and confident in who I am."


Amsterdam-based Branding Strategist

"I experienced a deep feeling of peace unlike anything I have ever experienced, both in the moments I was in the ceremony and that reverberated in me for months afterwards."


North Carolina Mom and three-time Synthesis Retreat Participant


There is a three-step process to participate in the Immersion Retreat Experience, ensuring your safety is our top priority:

STEP ONE Complete the Health Screening Questionnaire
STEP TWO Participate in a Video Screening Call
STEP THREE Sign the Agreement and Complete your Tuition Payment

IMPORTANT: While the majority of our Immersion Retreat participants report their experience was beneficial, individual experiences can vary widely, and can range from those who gain little to no positive benefits to those that suffer negatively from the experience. 


Our programs are not intended to diagnose or treat mental health disorders, and because safety is our top priority, a thorough health screening is required prior to being approved to participate in Immersion Retreat


You can find additional details about our health screening criteria here.

Our Approach

At Synthesis, we focus attention on the following six (6) conditions, each of which plays an essential role in every psychedelic journey:

  • Set: The mental attitude of a would-be psychedelic voyager.
  • Setting: The surroundings in which a psychedelic substance is ingested.
  • Guide: The program team who are all experienced with non-ordinary states of consciousness and equipped to mitigate challenges and channel insights.
  • Substance: The type and quantity of psychedelic agent; in this program, psilocybin.
  • Session: The entirety of a psychedelic trip, including all ancillary activities and rituals.
  • Situation: The environment, people, and culture a person comes to a retreat experience from and returns to afterwards.

When these elements are not carefully considered, and psychedelics are not used in a safe, supported, and structured setting, many of their potential benefits may not be experienced. 


That’s why Immersion Retreat includes the critical preparation and integration elements that anchor the psychedelic ceremony experiences. 


Because of the potentially powerful nature of psychedelic experiences, and the impact that sharing this experience with others can have on your psychedelic journey, we keep each Immersion Retreat program to between 15 to 20 carefully screened participants. 

Program Overview

Immersion Retreat is a Three-Part Comprehensive Experience:

  • Online Pre-Retreat Preparation Sessions:Inclusive of three (3) 75-minute sessions in the weeks immediately prior to the retreat
  • A 5-Day Experiential Retreat:
    Inclusive of two (2) psychedelic ceremonies
  • Online Post-Retreat Integration Sessions:
    Inclusive of three (3) 75-minutes sessions
    in the weeks immediately following the retreat

All participants will receive an Immersion Retreat Program Manual that contains important details, as well as a list of recommended resources.

Part One: Pre-Retreat Preparation Sessions

Setting the container for your experiential retreat begins weeks in advance. Our preparation process draws upon scientific research, as well as wisdom traditions, to get you ready for your experience. 


Ahead of the first preparation session, we ask that you begin to work with the intention setting process outlined in your Immersion Retreat Program Manual. The sessions are hosted by our professional facilitators and will include all the other participants in your program.


There are three (3) 75-minute Preparation Sessions:

  • Preparation Through Practice: Whether expert or novice, we come together with a beginners mind. In the first session, we begin by getting to know one another and focus on simple practices that help you connect to your deepest intentions for the journey ahead.
  • Awareness Through Active Listening & Noticing: Being the listener is one of the most simple, yet advanced practices on the path. Active listening is an art all unto itself; more than a skill, active listening is a way of being. In this session we focus on developing our listening into an integrated practice of deep-rooted listening to ourselves, others, and life.
  • Opening Up Around Resistance: Resistance is a powerful force for transformation. During this session, we will explore what resistance is, how it may be showing up in your life, and how resistance can show up during a psychedelic journey. Together we will walk through acceptance practices that support us to remain present and grounded.

You will emerge from the preparation phase with a unique intention to inform the experiential phase of your journey.

Part Two: A 5-Day, Experiential Retreat in the Netherlands

Retreats are Held at One of the Following Venues

HOLOS, Costa Rica


HOLOS is a retreat center nestled in the sacred Diamante Valley in Costa Rica. This emerald haven is a magical landscape of cascading waterfalls, lush jungle, and mountain peaks. Holos Retreat Center has a stunning bamboo air shala, a ceremony space that breathes with the rhythm of nature. Chefs provide nutrient-rich foods, much from their own lush vegetable garden. Relish the experience of being immersed in nature, with the open-sided shala, luxury glamping accommodation, outdoor showers, and the glorious Diamante Falls nearby.

New Eden, The Netherlands


New Eden is a unique residential retreat center, nestled within 50 acres of serene and tranquil meadow and woodland, just 90 minutes away from Amsterdam. For nearly 30 years, since August 1994. Beyond being a mere venue, New Eden provides an environment that is ideally designed for immersive and deep-dive experiences. Throughout your stay, you will enjoy comfortable and peaceful accommodations, and savour nourishing and tasty meals, lovingly prepared by our own retreat chef.

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Day 1: Your retreat begins the day you arrive at the venue. We will start with a welcome circle, followed by one-on-one facilitation meetings where you will clarify your intentions and confirm the dose for your first psilocybin mushrooms (or truffles) experience. The evening culminates in a group sound meditation experience.
Day 2: After morning practice and detailed instructions, you will participate in your first psychedelic ceremony using psilocybin mushrooms (or truffles). You will be fully prepared and made comfortable in a setting optimized for your needs, allowing you to make the most of your psychedelic experience.
Day 3: You will spend time integrating your first psychedelic experience while simultaneously preparing for your next one. The schedule includes group practices, integration workshops, and one-on-one meetings with an experienced facilitator.
Day 4: After morning practice and a guided workshop, you will experience your second psychedelic ceremony.
Day 5: The retreat’s final day centers on integration. You will participate in one-on-one and group integration sessions to begin processing your experience which will help support and enable you to integrate it more fully into your life.

You will emerge from the 5-day experiential retreat with a deeper understanding of the intentions that are guiding you and clarity around what you need to continue cultivating in your life as you prepare to return home.  

Part Three: Post-Retreat Integration Sessions

While preparation is essential for maximizing the potential of a psychedelic retreat, integration is critical for unpacking and understanding your experience and transforming it into your desired outcomes. During our three (3) virtual group Integration Sessions, you will explore how to move from the retreat experience back into your day-to-day life.


There are three (3) 75-minute Integration Sessions: 

  • Somatic Integration: Coming home with a renewed sense of possibility and vision is both an exhilarating experience as well as a potentially difficult one. Using a variety of integration tools, we will provide support in accepting the challenges, however they may arise. We encourage you to connect to what is empowering and nourishing, and to remain feeling everything as deeply as possible by attending to your body.
  • Social Integration: In a world where language around expanded states of consciousness is rare, and the experiences themselves are frequently and easily misunderstood, you may face challenges in speaking your new, authentic truth. You may encounter disagreement, judgment, and unfavorable responses from people in your life. In this session, we will address how to remain integrated in the social sphere and how to discern when and how much to share with others.
  • Synthesis - The Culmination of Elements: This will mark the last week of your Immersion Retreat, and in this session, we will bring the program together by reflecting and making an inventory of what has changed and setting intentions to remain connected moving forward. 

You will emerge from the Integration Sessions with a renewed sense of how to apply and embody the insights and learnings gained from this growth-enhancing experience to your everyday life, and equipped with the tools and practices to continue to evolve on your personal journey. 

Immersion Retreat

Juan Tepui Retreat Facilitator
Juan has studied music since childhood and music production at University. He became interested in psychedelics and their strong influence on music and consciousness from an early age. He has spent years in India practicing meditation and yoga in various ashrams. He studied the Bansuri flute with the legendary Pandit Hariprasad Chaurasia, and now teaches and makes Bansuri himself.

He has been dedicated to facilitating live music for meditation, healing, and psychedelic ceremonies for many years, for the Ayahuasca tradition of Colombian Shamans and increasingly for psilocybin journeys. Juan is passionate about the transformative power of psychedelics, what they can bring to humanity, and how they can help us heal our connection to nature and spiritual growth. CLOSE
Costanza Di Prisco Lead Facilitator
Costanza began working with psychedelics in 2012, initially as a participant, later as an assistant, then began training with shamans and healers, and eventually studied to become a Psychedelic Practitioner. Her last few years have been devoted to psilocybin, though she has worked with a variety of plant medicines. She is also a breathwork coach, working with the body’s knowledge to achieve understanding and promote healing. She has trained in Bioneuroemotion, a field that blends biology, neuroscience, epigenetics, NLP, and psychology. She received training in India to be able to instruct in meditation, yoga, and pranayama. She has finished a master plant dieta with Noya Rao and follows the tradition of the Shipibo from Peru in terms of shamanic techniques.

Her facilitation style combines ancient wisdom methods with cognitive therapeutic techniques from the West to produce powerful transformational experiences. When singing in ceremony, Costanza places emphasis on the healing potential of music. Her goal is to serve as a bridge for people seeking to start or continue their own journeys of self-discovery; creating safe spaces so others can engage in their psychedelic healing experiences feeling supported and empowered so their own inner wisdom can emerge. CLOSE
Gabriele Cotronei Retreat Facilitator
For over a decade, Gabriele has studied the human mind, beginning with its formation in utero and early infancy, in relation with the primary caregivers. This entailed training in non-verbal communication approaches, psychoanalytic therapy and infant observation, Jungian sand play therapy, and traditional Chinese medicine.

He has worked in various public mental health settings, where he co-created safe containers with patients and clients to support a non-judgmental exploration of themselves and find healing in mind, body, and spirit.

This curiosity for the human experience led him to delve into spirituality, Eastern philosophies, and yoga. Psychedelics were a natural progression in his personal healing journey, allowing him to experience the depths of joy and the transformative power of the relationship with entheogens. Through this relationship he has dived deeper into somatic approaches. He passionately co-develops safe spaces centered around the imagination, creativity, and interconnectivity. Through his work he is able to grow and align with his vision, by engaging in deep and meaningful work that contributes to a culture of healing. CLOSE
Mary Bredin Retreat Facilitator
Mary is a psychotherapist with over 30 years experience of working in a variety of UK healthcare settings as a clinical supervisor, group facilitator, researcher, and educator. She specializes in helping people face loss and change, illness, and death, and is particularly interested in how nature connection, mindfulness, self-compassion, and vision quest rites of passage can support journeys of personal growth, transformation, and healing. In her spare time, she tends an old Cornish garden, which has lots of flowers and brambles. She swims in the sea all year round and loves to walk in wild places. CLOSE

Program Dates



August 1 - 5, 2024 — New Eden, The Netherlands


New Eden, The Netherlands, August 1 - 5, 2024


A 7-Week Program inclusive of Preparation, a 5-Day Psychedelic Retreat in the Netherlands, and Integration

Program Tuition**: $5,797

Each retreat can accommodate 15 to 25 participants. Registrations will be confirmed based on the order in which Health Screening Questionnaires are completed, and tuition payments are received.

**Travel costs to and from the Netherlands are not included.
Pay In Full: $5,797.
Two-Installment Plan: 2 payments of $2,898.50 each.
The Two-Installment Plan is not available if you sign up less than one month before the retreat start date.


Frequently Asked Questions

Why is a health screening required?

At Synthesis, safety is our number one priority. Although the psychedelic retreat experience can be beneficial for many, for some it’s not appropriate to consume psilocybin. These include people who have medical contraindications relating to their physical and mental health. Our health screening process aims to mitigate the risk for participants, and we have a dedicated team that assesses each health screening using informed guidelines.  

Are there any specific conditions or health contraindications that would make me ineligible for the program?

The following are considered contraindications that would deem someone ineligible to participate in the program. These include, but are not limited to:

  • Suicidal thoughts or attempted suicide
  • Schizophrenia
  • Psychosis (including mania)
  • A personality disorder, including borderline personality disorder
  • Psychiatric hospitalization
  • Any dissociative disorder, including dissociative identity disorder
  • Self-harm or self-destructive behavior. Examples include: cutting, bruising, burning or similar self-inflicted wounding, self sabotage, excessive drug and/or alcohol use for multiple days with little to no sleep, regular high-risk sexual behavior, etc.)

What kind of support is available during the retreat?

Our Facilitation Team includes a Lead Facilitator as well as Retreat Facilitators, all of whom have been carefully trained and supervised by our Lead Facilitator to support you during your journey. Our retreats have approximately one (1) support staff for every two to three (2-3) participants.

What type of mushrooms do you use in your retreats?

In Costa Rica, Synthesis use psilocybin mushrooms. In the Netherlands, Synthesis uses a tea made from truffles, an earlier stage of mushroom development that still contain psilocybin and has psychedelic effects if ingested.

How do you decide what dosage a participant receives?

Deciding on dosage is a collaborative and consent-based process. You will discuss dosage in a one-to-one facilitation session on-site at your retreat.

In Costa Rica, generally speaking, the first dose is approximately 1g or 1.5g of psilocybin mushrooms. The second dose can be up to a maximum of 3g of  psilocybin mushrooms.

In the Netherlands, generally speaking, the first dose is 15g of truffles containing psilocybin. The second dose can be up to a maximum of 30g of truffles containing psilocybin.

Where do the retreats take place?

Our retreats take place at two locations: Costa Rica and The Netherlands. Scroll up to the Venue section.

What are the accommodations like?

New Eden: The accommodations are located in one building throughout the grounds and include a mix of single and double rooms. All accommodations are simple and clean, with private toilets.

Holos: The accommodations are luxurious glamping tents that are located throughout the grounds and include a mix of single and double rooms. All accommodations are simple and clean. Bathrooms and showers are mixed-sex, gender-neutral spaces. There is one private bathroom and shower for your convenience.

Room assignments are made at the discretion of a retreat team member, and we cannot guarantee participants single rooms. We will do our best to accommodate family members who wish to stay in double-occupancy rooms whenever possible.

Single participants will be allocated rooms with single beds, separated by gender. If you’re a woman attending alone, you would be sharing with another woman. Couples attending together will share a double room.

Does the venues accommodate special food preferences or dietary restrictions?

The food at our venues is vegetarian, organic, seasonal, and local. Coffee, teas, fresh fruit, and nut snacks are available between meals. The kitchen will cater for any individual dietary requirements and/or lifestyle preferences. We will collect dietary information from participants prior to your retreat.

Is transportation available to the venues?

Participants are responsible for arranging transportation to and from the venue. Synthesis recommends the Staxi taxi service which can be reserved and booked in advance. Additional transportation recommendations can be provided upon request.

What is your cancellation and refund policy?

Time Frame Time
120 or more days from start date Entire amount the client has paid, less $500 processing fee
90 -119 day from start date 50% amount the client has paid, less $500 processing fee
60-89 days from start date 25% amount the client has paid, less $500 processing fee
59 or less days from start No refunds

Is there a tuition payment plan available?

Yes. After your Health Screening Questionnaire is approved, you will be prompted to sign the service agreement and select your tuition payment preference. 

You can pay your tuition of $5,797 in full. Or, you can make two payments ($5,797 + $100 finance fee for a total of $5,897). You can contact us for more information and for signing up to the plan. 

If you select the payment plan, you will be charged half at the time of registration and the balance 30 days from the registration date. The same payment method used for the first payment will be used for the second. 

Do you offer scholarships?

Financial Scholarships are currently not available. If you are in need of a scholarship to participate in the program, please do not complete a Health Screening Questionnaire and instead click here to be added to our scholarship interest list.


We are currently in the process of securing funding and building a fair and equitable process for reviewing and approving scholarship applications for Expansion.

What if I have a conflict with the online Preparation and/or Integration Sessions?

Attendance at the online Preparation and Integration sessions is mandatory and integral to your program experience. Although occasional exceptions can be made due to extraordinary or critical circumstances, we encourage you to be sure you can attend each of these sessions in advance of registering for the program.

Have more questions?