Eye-to-eye connections & spirited conversations.
Analog experiences & fleeting moments.
We host salons.

POSTHOC is a petri dish for ideas and thought-leaders. We host invite-only gatherings that connect people and spread ideas.


POSTHOC provides the medium for our clients to build movements and grow communities. We raise awareness around ideas and topics, and blow them up for the world to hear about them. We create the setting for trusted connections to flourish from our deep worldwide network. We secure exposure for our clients among influencers that matter to you.

POSTHOC creates unique, intimate experiences that stir the senses—a forum for the cross-pollination of ideas and conversations. We believe you can have fun while changing the world.


Susan MacTavish Best is the founder of POSTHOC. She has more than 20 years of experience creating communities of influence around brands, ideas and people, and she has been at the forefront of intimate and curated experiential marketing.

She was the founder and CEO of Best Public Relations, a boutique PR firm based in New York and Silicon Valley. For two decades, her firm took little-known startups and turned them into household names with high valuations. In 2011, she launched the lifestyle brand Living MacTavish.

Susan has hosted hundreds of gatherings and salons around the world on a diverse range of topics. She brings together eclectic, curated groups of people in one room and encourages them to look each other in the eye and have a spirited conversations that lead to deeper, emotional connections.
Susan sits on the advisory board of the Quantitative Biosciences Institute at the University of California San Francisco. Susan has been on the advisory board of a handful of startups and has worked closely mentoring many entrepreneurs.

Susan graduated from Hamilton College with a B.A. in history. She is a long-distance trail runner. Susan grew up in Scotland and attended St. Leonards School in St. Andrews. She was born on Prince Edward Island.

Past Salons

Pete Worden: Search for Life in the Universe, Intelligent or Otherwise with DJ Nicks

New York, 2018

Susan MacTavish Best interviewed Pete Worden. Pete is chairman of the Breakthrough Prize Foundation and executive director of Breakthrough Initiatives.

Intelligence Up, Down & All Around with the Templeton World Charity Foundation and Icarus

London, May 2018

We debated the boundaries we know about human and animal intelligence with Dora Biro and Marta Halina. They drew from research on animal and human intelligence to discuss the future of AI and how we would recognize intelligences that take radically different forms. Dora is a professor of animal behavior at Oxford and Marta lectures on the philosophy of psychology and cognitive science at Cambridge. Living MacTavish co-hosted with Templeton World Charity Foundation. Breakout U.K. trance duo Icarus spun on the decks.

Warlords, Oligarchs + Marianne Aya Omac & Gabe Harris Live

New York

Susan interviewed Tom Burgis, investigative correspondent for Financial Times, about his life and experiences as a reporter. She also dove into the stories and people behind Tom’s writings of corporate misconduct, the arms trade, the oil industry, money laundering, the plundering of minerals, the shady underbelly of our species and the world we live in. Joan Baez’s mentee, Marianne Aya Omac, and Joan’s son, Gabe Harris, performed on Susan’s roof.

Rock & Robots

New York

An evening with Ken Goldberg, UC Berkeley robotics professor, filmmaker and artist, plus a live performance by Australian singer-songwriter Sun Rai. Susan interviewed Ken about robotics in the workplace, the singularity, etc. (See Ken’s op-ed in The Wall Street Journal, inspired by a debate at the salon with the WSJ editorial features editor James Taranto.


Artists & Criminals on the Edge of Technology

San Francisco

Susan moderated a conversation between NPR’s Laura Sydell and data artist Laurie Frick in advance of the series Laura produced for All Things Considered the following week.

Michael Pollan & Amanda Feilding, Countess of Wemyss: Psychedelics as Therapy

San Francisco

An evening with writer Michael Pollan and Beckley Foundation director Amanda Feilding. Susan interviewed Michael and Amanda about psychedelics and current research into their medical benefits.

Brass & Brotopia

New York

An evening with Bloomberg technology anchor and Brotopia author Emily Chang. Susan interviewed her about her life and recent work on the male-dominant culture of Silicon Valley and its long-term implications on society. A trumpet quintet performed live on the roof.

Are We Ready For Virtual Immortality?

San Francisco

Featuring science fiction author David Brin, physicist Andrei Linde, and Christof Koch, who runs the Allen Institute for Brain Science.

All in the Mind? and Performance with Garrin Benfield

New York

Susan interviewed British science writer Jo Marchant, author of CURE: A Journey into the Science of Mind Over Body. Can our minds heal our bodies?

Plant Intelligence with Monica Gagliano and DJ Tuff Ghost (two sets)

San Francisco, 2018

Susan interviewed evolutionary ecologist Monica Gagliano.

The Edit: An Evening with Jennifer Doudna, CRISPR coinventer

San Francisco

Susan interviewed UC Berkeley biochemist Jennifer Doudna about her life and work on gene editing. Brass Quintet performed.

An Evening of Sleep Stories

San Francisco

This respite of an evening from the holiday hubbub celebrated the launch of Calm’s Sleep Stories, available within the Calm app.

An Off The Record Evening with NPR Editors

San Francisco

Susan hosted the NPR business and tech editors from New York, San Francisco and Washington, D.C., and 25 Silicon Valley influencers to discuss future story ideas. What should NPR be covering about Silicon Valley?

An Arctic Living MacTavish Salon

The Arctic Circle, Longyearbyen, Svalbard

Susan was invited to host the closing night salon on a small group Martha Stewart took to Svalbard’s Global Seed Vault, 400 miles south of the North Pole. Included readings from Susan and actresses Minka Kelly and Sophia Bush.


Who’s Hacking Our Bodies & Brains?

Susan interviewed Dr. Robert Lustig, author of the book The Hacking of the American Mind: The Science Behind the Corporate Takeover of Our Bodies and Brains. Dr. Lustig is well known for his anti-sugar crusade in America, and for promoting global metabolic health and nutrition. His online talk about the risks of sugar has now been viewed more than 8 million times.

An Algorithmic Night of Whisky

New York & San Francisco

A tour and tasting with a master distiller of the single malt whiskies of Scotland using Quid’s software. A tasting menu accompanied the various scotches.

Hidden Cameras, Covert Missions

New York & San Francisco

Susan moderated a conversation with Videre CEO Oren Yakobovich about his life and work as an entrepreneur at the intersection of technology, human rights, citizen journalism and filmmaking. How does one use technology and visual information to create sustainable, lasting, positive change in areas of conflict – areas too dangerous for news organizations to send their reporters?

The Future of Farming – The Future of Food

New York

Susan moderated a conversation with Tobias Peggs, cofounder and CEO of Square Roots, and Danielle Gould, founder and CEO of Food + Tech Connect.

The Way Out of Black Holes with Theoretical Physicist Andy Strominger

San Francisco

Andy heads up the Center for the Fundamental Laws of Nature at Harvard. He is well known for his work with Stephen Hawking on black holes.

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