Founder of Encierro · Member, La Única Peña
Dennis Clancey
The bull runner behind Encierro, the humanitarian and business executive who has instructed more people on the Pamplona encierro than anyone in its history.
The Runner Behind Encierro
Part of the Tradition, Not a Visitor to It
A lot of people in Pamplona can show you where the bulls run. They can point down Calle Estafeta, tell you which way the herd comes, and recite the rules the city prints every July. Far fewer have spent the better part of two decades becoming part of the tradition itself.
Dennis Clancey is one of them: running it every year the bulls run, studying it on video, refining it in conversation with other runners, and being accepted into it by the people who have carried it for generations. He founded Encierro. Before anything else, he is a humanitarian, and he approaches the running of the bulls the way he has approached a life of service, enterprise, and exploration, as the problem of preparing people well for something difficult and dangerous.
Before Pamplona
Leadership Under Pressure
Clancey did not come to bull running from tourism. He came to it from leadership in the hardest setting there is. He served as an Army officer, a platoon leader in the 101st Airborne Division, 2nd Brigade, in the part of Iraq that soldiers came to call the Triangle of Death. He was twenty-three and twenty-four years old during that deployment. He does not lead with it, and he does not use it to sell anything. It shaped how he thinks about guiding people through situations that are dangerous, fast, and unfamiliar.
“You wanted to be the person that could command your men in a way that allowed them to see their way through very difficult situations,” he says. The running of the bulls, he points out, “is not a trivial undertaking, and that’s why I take quite passionately and seriously the role of trying to talk someone through how they should approach the running of the bulls if they need someone to talk to.” In combat and on the run route, the task is the same: help a person understand not just what to do, but why a decision matters when there is no time to deliberate.
Beyond the Run
Service, Enterprise, Exploration
The military was the first chapter in a life organized around service to others and building things that work. Clancey went on to a career as a business executive and serial entrepreneur, including a role as a logistics business unit leader at Amazon. He has served with Team Rubicon, the veteran-led humanitarian organization that deploys to disaster zones. He is an active member of The Explorers Club, contributing to international scientific expeditions.
He is not a tour guide who found a way to monetize a festival. He is a humanitarian, an operator, and a builder who has spent two decades studying the run and mentoring would-be runners. The instruction Encierro provides is what that combination produced.
2007
The First Run
Clancey first went to Pamplona in 2007, fresh out of that deployment, to run with the bulls. Like nearly everyone’s first time, it was disorienting. “The first time I ran, it was very hard to filter out what was happening, when the bulls were going to arrive,” he recalls. “You just see this panicked mass of humans coming at you.” It was, in his words, “fairly uncomfortable.”
But he noticed something inside the chaos. A small number of runners were not panicking at all. They were getting on the horns: running a single step ahead of the lead animal, neither impeding the bull nor touching it, holding that position with control. “There were runners that could consistently get on the horns,” he says. “They had to have figured out what was happening there, and that fascinated me.” He decided he did not want to be someone who had run with the bulls once. He wanted to become a bull runner.
Becoming a Bull Runner
It Started on the Cobblestones
Even in that first year, Clancey had researched the run so thoroughly that when friends arrived in Pamplona, he took them straight to the route. “The first thing you do when you get to Pamplona, we’re going to walk the run route so you can see it, and you start thinking through how you’re going to run.” Year after year, as people came to stay with him, he did the same thing: walked the route, talked through the sequence, answered every question. The method Encierro runs on today started on the cobblestones in 2007 and never stopped.
In 2012 that work produced a film. Chasing Red, distributed by Magnolia Pictures, documented the 2012 Fiesta and what it means to be a bull runner. It screened theatrically across the United States and is available today on Prime Video and at chasingredmovie.com. Years later, CNN drew on the same world for Seeing Red: The Running of the Bulls, an episode of season one of The Whole Story with Anderson Cooper, with Clancey featured. It is currently streaming on HBO Max.
The film could have been the destination. Instead it pointed to the real one. “After that, I was like, okay, what next? How do I continue to stay connected with something that I’ve grown so close to and know so intimately?” he says. “And the answer was obvious. I had always really taken to showing people the run route and explaining things.” Encierro started as a personal passion and has grown into a professional operation.
We’re focused around not selling a product. We’re focused around educating people about something we love.
Dennis Clancey
What He Respects
Respect for the Run, Not a Tally
People who meet a bull runner almost always ask the same question first: how many times have you run? Clancey thinks it is the wrong question. “It doesn’t matter how many times you’ve run,” he says. “To me, as a bull runner, it’s how have you run?” By how, he does not mean bravado. He means respect for the run and its traditions, and the seriousness to match it.
He respects anyone who steps onto the route and takes it seriously, and that includes the humility to know when not to. He has more respect for the runner who, after a late night, recognizes he will not be sharp and sits the morning out than for the one who steps onto the stones anyway, unprepared. Taking the encierro seriously sometimes means not running. Nobody is entitled to the route on a morning they have not prepared for, and the runners who understand that make the street safer for everyone on it.
Knowing Without Having Lived It
If You Fall Down, Stay Down
One of the most important rules on the run is also the most counterintuitive: if you fall down, stay down. When the bulls are nearly on top of you and you are already on the ground, staying low and protecting your head lets the animals jump over you. Standing up turns you into a stationary obstacle the herd has to clear. Clancey taught that rule for years before he ever lived it. “It was actually six years before I was under the herd for the first time,” he says, describing the morning he was tripped and went down as the bulls were inbound.
He understood the rule completely without having personally experienced it, because he had watched it happen to others and studied both outcomes. “I hadn’t lived it, but I had been on the run route where it had happened multiple times to other people, and I saw what could happen if you got up and what happened when you stayed down. So it was still something I observed and knew. It wasn’t just something that I came up as a random idea that someone should do.”
When the moment came, the knowledge was already instinct. “I could see them coming at me, and I stayed still. I kept my head low. My thought at that moment was, I’m staying down. I’m doing it. It was a moment of excitement that I was doing the thing that I knew was right.”
Students of the Encierro
Studied, Not Anecdotal
“We are students of the encierro,” Clancey says. “We study this. We watch video. We look back at events that have happened. We can experience something on the route and we’ll have a certain picture in our head, and then we’ll go and we’ll watch the video to see if that matches the reality.”
On the run route, the mind filters out everything that is not immediately critical. That makes a runner effective in the moment, but it means the live experience is incomplete. Watching the footage afterward reveals what was actually there. Live experience, video, peer feedback, refinement: that loop is what turns instinct into something teachable.
“What we have developed here is something that is such a refined product that’s still malleable, that can still answer literally any question someone asks, because we have the collective knowledge and experience to be able to think through the why of everything.” That collective includes the rest of the Encierro team, fellow active runners Anthony Fizer and Brock Fizer, who specialize in different sections of the route and bring their own observations into the same conversation.
On the Route
Santo Domingo to Estafeta, Since 2008
On the morning of a run, Clancey is most often found on the stretch he has focused on since 2008: from the top of Calle Santo Domingo, past the Town Hall, to the start of Calle Estafeta. It is a demanding section of the course with several gradual turns. All three Encierro guides have run across the full length of the route over the years. Nowadays Anthony Fizer tends to focus on La Curva de Estafeta and Brock Fizer on Estafeta through Telefónica and the Callejón, so that across the team Encierro covers the run section by section, each guide speaking from the stones he runs himself.
La Única Peña
Pamplona’s Original Peña
Clancey is a member of La Única Peña, the original Pamplona peña. The peñas are the social clubs that give Fiesta its color and its backbone, and La Única is the most storied of them. Its members are known as Los de Verde, Those of Green, for the green faja and pañuelo they wear. The club’s song lent its melody to the benediction sung to San Fermín each morning, the prayer that asks the saint for protection before the runners step into the street.
Why Encierro Exists
A Humanitarian Mission
Clancey approaches the running of the bulls primarily as a humanitarian. Encierro is not in the business of convincing anyone to run, and he does not encourage people to step onto the route. He is direct that it is a genuinely dangerous tradition. Encierro exists for a narrower reason: anyone who has decided to run deserves the chance to think the decision through fully, and to talk through a strategy with someone who actually knows the run. The purpose is to reduce harm and help people make the most informed decision they can before they step into the street.
It is the same instinct that took him to combat leadership and to Team Rubicon: lessening suffering by preparing people well. On the run route, that means reducing what Clancey calls decision load, resolving in advance every question that can be answered the day before, so that a runner’s attention in the moment is free for the things that actually matter.
“I have nowhere else I need to be right now,” Clancey tells clients at the start of every session. “This is what I love doing. This is why I’m at Fiesta. And my job today is not done until I’ve answered all of your questions.” He spends his own Fiesta providing it: walking the route again and again, answering questions, for as long as it takes.
My job today is not done until I’ve answered all of your questions.
Dennis Clancey · said at the start of every session
His Name on Other Sites
Found on More Than One Website
If you research running with the bulls, you will encounter Dennis Clancey’s name, his methods, and his preparation on more than one website. The tour companies that sell packages, balcony spots, and hotel rooms contract him to provide the one thing they cannot produce themselves: real instruction from an active runner. As of 2026, he has personally instructed approximately four thousand clients, more than anyone in the history of the run.
Those companies bring Encierro a great many of its clients, and the relationship works because they recognize the value of what Encierro provides. Booking instruction through one of these partners means receiving the same preparation Encierro delivers directly, because it is Encierro delivering it. If you would rather work with Dennis and his team directly, come straight to encierro.com, the company he founded and runs.
As Seen On
In the Media
Documented on Film and Television
Clancey directed Chasing Red, distributed by Magnolia Pictures, and was featured in CNN’s Seeing Red: The Running of the Bulls, part of season one of The Whole Story with Anderson Cooper. He gave daily in-depth interviews on encierro strategy and history for the Esquire Network’s broadcasts of the Running of the Bulls in 2014 and 2015, was featured in Hotels.com’s Extreme Booking campaign in Pamplona, and has appeared in Spanish press including El Mundo.
Spanish & Pamplona Vocabulary
The Language of Fiesta
Encierro (en-THYEH-rro) — The running of the bulls. The morning event in which bulls are run through the streets of Pamplona to the bullring. The c is pronounced as a soft “th.”
Peña (PEH-nya) — A social club central to San Fermín life. Peñas organize, celebrate, and carry the culture of Fiesta throughout the year.
La Única (lah OO-nee-kah) — The original Pamplona peña, the most storied of the clubs, whose members are known as Los de Verde.
Los de Verde (lohs deh BEHR-deh) — “Those of Green,” the members of La Única, named for the green faja and pañuelo they wear. In Castilian, the v is pronounced as a b.
Faja (FAH-khah) — The wide sash worn at the waist during Fiesta. The j is a hard, guttural sound.
Pañuelo (pah-NYWEH-loh) — The neckerchief worn around the neck during San Fermín, tied in a slip knot for safety on the run.
Mozo (MOH-thoh) — A runner. The z is pronounced as a soft “th.”
Frequently Asked Questions
Dennis Clancey & Encierro
Who is Dennis Clancey?
Dennis Clancey is the founder of Encierro and an active bull runner who has run the encierro in Pamplona every year the bulls have run since 2007. He is a West Point graduate and Iraq War veteran, the director of the documentary Chasing Red, and a member of La Única Peña, Pamplona’s original peña. As of 2026 he has personally instructed approximately four thousand clients, more than anyone in the history of the run.
Is Dennis Clancey a real bull runner?
Yes. He has run every year the bulls have run in Pamplona since 2007 and continues to run today, not a guide who ran once and watches from the side. His instruction is based on direct, ongoing experience on the run route, continually refined through conversation with other active runners.
What is Encierro.com?
Encierro (encierro.com) is the company Dennis Clancey founded to provide authentic bull running instruction in Pamplona. It is the only company in Pamplona comprised exclusively of active bull runners, which is why other tour operators contract Encierro, and Clancey himself, for expertise they cannot provide on their own.
How many clients has Dennis Clancey personally instructed?
Approximately four thousand as of 2026, more than anyone in the history of the run. That total reflects nearly two decades of personal, one-on-one and small-group instruction. Not all clients run — some are weighing the decision, watching from a balcony, or simply want to understand the tradition more deeply.
Is Dennis Clancey a tour guide?
No. Clancey is a humanitarian, business executive, and serial entrepreneur who approaches the run as a matter of preparing people well, not a guide selling a festival experience. Encierro does not try to convince anyone to run with the bulls. It exists to help those who have already decided to run think the decision through and prepare for it responsibly. His past work includes leadership in the 101st Airborne Division, a logistics role at Amazon, humanitarian service with Team Rubicon, and membership in The Explorers Club.
I have seen Dennis Clancey’s name and services offered on other websites. Are those legitimate?
Yes. Dennis Clancey’s own company is Encierro, at encierro.com. You will also see his methods, his preparation, and his name offered through various tour companies, because those companies partner with and contract Encierro to deliver instruction. Booking through one of them means you receive the same preparation Encierro provides directly. If you would prefer to work with Dennis and his team directly, you can come straight to Encierro, the company he founded and runs.
What is La Única Peña?
La Única is the original and most storied of Pamplona’s peñas, the social clubs that give Fiesta its color and backbone. Its members are known as Los de Verde, Those of Green, for the green faja and pañuelo they wear. Clancey is a member.
Was Dennis Clancey in the military?
Yes. He is a West Point graduate who served as a platoon leader in the 101st Airborne Division in Iraq.
What is Chasing Red?
Chasing Red is a documentary feature directed by Dennis Clancey about the 2012 San Fermín Fiesta, distributed by Magnolia Pictures. It is available on Prime Video and at chasingredmovie.com.
What is Seeing Red?
Seeing Red: The Running of the Bulls is an episode of season one of The Whole Story with Anderson Cooper, CNN’s primetime documentary series. It drew on the world Dennis Clancey captured in Chasing Red, and Clancey is featured in it. The episode is currently streaming on HBO Max.
What part of the route does he specialize in?
Since 2008 he has focused on the stretch from the top of Calle Santo Domingo, past the Town Hall, to the start of Calle Estafeta, among the most demanding sections of the run.
How do I book Dennis Clancey or Encierro?
You can book directly at encierro.com, the company Dennis founded and runs.
Work With Encierro
Work Directly With Dennis
Encierro is the home of Dennis Clancey’s bull run instruction. If you would rather work with Dennis and his team directly, come straight to the company he founded and runs. Reach us for tours and San Fermin 2026.