Travelers are all about the boutique hotel trendbut what exactly is a boutique hotel'Business Insider spoke with four industry experts, including legendary hotelier Ian Schrager and director of the annual Boutique Hotel Awards Shlomo Gabbai, to get to the bottom of it."In truth, there is no official definition," Gabbai said.Visit Business Insider's homepage for more stories.In 2019, a boutique hotel on a remote, private island in Norway owned by polar explorer Brge Ousland debuted three eco-friendly "sea cabins" on the edge of the Barents Sea. Clad in aluminum and featuring a waterside glass wall, they cost a minimum of $390 per night, are only accessible by ferry from the mainlandand are already booked into September.Manshausen Island 2.0 is just one example of the boutique hotel rage that seems to be sweeping the world. The term has 1.5 million hashtags on Instagram and has been used to describe everything from an art-filled hotel with apartment-style rooms in downtown Ashevilleto cocoon-like suites with infinity pools on an island in Santorini. There's even a committee that spends an entire year visiting boutique hotels around the world and judging the best accommodations.So what, exactly, is a boutique hotel' They have a certain je ne sais quoi, but beyond that, no one quite agrees on what they are.To get to the bottom of this question, Business Insider spoke with four industry experts: Ian Schrager, the legendary hotelier behind boutique hotel brands EDITION and PUBLIC; Shlomo Gabbai, director of the annual Boutique Hotel Awards, which recognizes excellence among luxury boutique hotels around the world; Deanna Ting, author of "The Complete Oral History of Boutique Hotels," a 60,000-word longform article published in 2016 that focuses on the development of boutique hotels in the US; and Bjorn Hanson, who retired as a professor at NYU's Jonathan M. Tisch Center of Hospitality and now works as an industry consultant.But from the size of the establishment to the details that make it "boutique," there was only one aspect of boutique hotels that all four agreed on: The term has evolved over time and will continue to do so.As Gabbai put it, "In truth, there is no official definition."Boutique hotels are rooted in a sense of place and evoke a "special" feeling"Special" is the word that surfaced most in conversationTing, Gabbai, and Hanson all used it at least once."Boutique is maybe just like another way of saying 'special' or 'memorable' or 'different,'" Ting told Business Insider. "That's kind of what everyone is looking forthat magic."Gabbai agreed. In 2019, the Boutique Hotel Awards judging panel received over 300 hotel nominations spanning 80 countries. They whittled the list down to 15 "world's best" winners, ranging from World's Best Beach or Coastal Hotel and the World's Most Inspired Design Hotel to the World's Best Wellness Spa."There are an infinite number of recipes, but the key ingredients I see in a boutique hotel are individuality and a great emotional impact," he said.Schrager, meanwhile, described the experience of a boutique hotel as "elevated.""It has to appeal to a certain sensibility as much as if it were demographic. It's all about the attitude," he said.The experience of a boutique hotel begins the moment a guest walks in the door, according to Hanson. "At the end of the first minute, someone at a boutique hotel should feel like he or she is being kind of captured with whatever that experience is," he said.A range of factors can create this experience. "It can be the location, architecture, design, history or just something clever that is part of a theme," Hanson said.Boutique hotels are also often rooted in a sense of placeone that appeals not just to travelers, but locals as well."It's not meant to just be a place where people check in, check out. It's meant to be a fixture of that specific community that it is part of," Ting said.Consider ACE hotels, a chain of art-filled boutique hotels that opened in Seattle in 1999, has branches across the US and London, and will be opening in Kyoto and Toronto later this year. The hotels' lobby bars, seating areas, and event spaces often seem to draw as many locals as guests.Boutique hotels have been around for decadesand today's boutique hotels don't look like the early onesBoutique hotels emerged in the US beginning in the 1980s. Credit for the first boutique hotel is largely given to either Bill Kimpton, who launched his first Kimpton hotel in San Francisco in 1981, or Ian Schrager and Steve Rubell, who launched the now-closed Morgans Hotel in New York City in 1984. Both sets of hoteliers, as Ting and Schrager put it, created an experience different than the chain brands at the time."Anouska Hempel could [also] lay a strong claim with her design of The Blakes Hotel for launch in 1981," Gabbai said, though he noted the difficulty of determining the first boutique hotel. "Finding the first is as hard to pin down as the definition of a boutique hotel itself," he said.Schrager, who is often cited as the father of boutique hotels, noted that he and his partner Steve Rubell started using the term "boutique" in a retail analogy to compare Morgans Hotel to larger chains.Placing a heavy emphasis on design, they set out to become places where not only travelers, but also locals went, according to Ting."We were trying to say that all the other hotels were like department storesthey were trying to be all things to all peopleand we were like a boutique," he said.In terms of size, boutique hotels started out small, less than 100 rooms by various estimates. Placing a heavy emphasis on design, they set out to become places where not only travelers, but also locals went, according to Ting. Over time, boutique hotels have increased their scale and branding efforts and are no longer found just in urban centers, she said.The line between boutique hotels and mainstream hotels is blurringChanging traveler tastes and technology have also opened the door for larger brands to follow the boutique hotel model.Beginning in the '90s, hotel chains, with W Hotels leading the charge, started recognizing the boutique hotel model as a concept they could adopt, Ting said.Large hotel brands used to prize uniformity, highlighting "no surprises" in their advertising, according to Hanson. Today, uniformity doesn't carry the same weight."Travelers are looking for something that's genuine, that respects local materials and culture and traditions and food," he said.Boutique and independent hotels started off as synonymous, but that's no longer the case. Kimpton is one example: While it retains its "boutique" identifier, Intercontinental Hotels Group acquired the brand in 2015.What this all means in practice is that it's often difficult to identify, simply from appearance and branding, whether a hotel is boutique or not.Boutique hotels constantly adapt to the changing expectations of travelers. Instead of prescribed standards, modern travelers want to experience something novel when they're on the road. It's an appetite that social platforms are fueling."Now we don't need that uniformity to avoid unpleasant surprises because between guests posting about experiences and being able to do 3D tours of hotels, now we can not rely on that uniformity to have a good experience," Hanson said.Size doesn't define a boutique hotelunless it takes away from that "special" boutique feelingWhether or not a boutique hotel can have too many rooms was a polarizing subject."In our awards, we consistently find that judges record a lack of intimacy and an accompanying loss in the emotional impact that comes with it when hotels push at the upper 'limits' of what might be considered a boutique-sized hotel," Gabbai told Business Insider. "This is somewhere around 85-100 rooms. Although it doesn't make standard business sense to stop doing what works on a bigger scale, in boutique hoteliering, it's crucial."Schrager agreed with Gabbai on loss of impact, but not on size. A hotel stops being boutique, he said, only "when it loses its point of view and specific attitude ... when it becomes generic and institutionalized, cookie cutter."Even if EDITION had one thousand hotels worldwidewhich Schrager hopes could be a possibility one dayit could still be a boutique hotel brand, he said.At that scale, though, there's a tendency to standardize. When a hotel company becomes too big with its brand, "it starts to find ways to discover efficiencies and take what works best in multiple locations and apply it to other locations. That's when the boutique character is lost," Hanson said."A boutique hotel stops being a boutique hotel when it stops providing an experience for its guests," he added.Ting agreed. "I think it's hard to use size or number of rooms a qualifier for that anymore. I think it's when you lose that feeling of being in a special place or having a special experiencethat's when your boutique hotel card is removed."Now that more hotels are trying to be "different" and "special," they face the danger of ultimately looking the sameWith an eye on the future of boutique hotels, all four experts had a sense of how the concept will transform in the coming years and what issues it will face. As Schrager put it, the hotel industry is at risk of "falling into the same trap that it always falls into. They all start to look like each other."Everyone trying to replicate the boutique hotel model is the industry's "hamster wheel," Ting echoed.Schrager shared his theory that as society divides more deeply into two groupsthe 1% and everyone elsehotels will do the same. "Hotels follow what the people are doing," he said. In the future, there will be two main types of hotels: small, incredibly expensive hotels, and hotels for the rest of the population, Schrager predicts.In order to continue to deliver on the boutique hotel's promise of a special experience in a sea of hotels promising the same, Hanson, for his part, predicts that hotels will resort to using an increasingly high-tech, flashy set of techniques to differentiate themselves. Hanson sees hotels adding devices where guests can change the color of the walls with the flick of a remote device, or even change the firmness of a pillow, in order to continue to deliver on the boutique hotel's promise of being special.SEE ALSO:The top 18 boutique hotels in the world that should be on every luxury traveler's listDON'T MISS:A network of 28 tiny, one-bed hotels in Amsterdam is being called the most beautifully designed hotel of 2019 ' and it consists of a series of converted bridge houses. 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