Hilton Worldwide and Marriott International last week announced back-to-back plans to beef up their luxury and lifestyle brands to cater to younger — and higher-end — travelers.

McLean-based Hilton on Monday introduced Curio, a collection of boutique hotels that will operate under the company’s umbrella. The first round of hotels to join the brand includes the SLS Las Vegas Hotel & Casino (scheduled to open on Labor Day) and the Franklin Hotel in Chapel Hill, N.C. Each property will keep its name.

“There is a whole segment of traveler that is looking for a unique experience — a hotel that celebrates the local area or is a little bit quirky,” said Rob Palleschi, senior vice president of brand management for Hilton. “We want to own that customer.”

By the end of the year, Hilton expects to have signed deals for 25 Curio properties, including hotels in the Middle East and Asia. The company is also looking to add Curio hotels in the Washington area, Palleschi said.

“Our customers and owners have expressed strong interest in a brand from us that includes hotels that can retain their unique identity,” Christopher J. Nassetta, president and chief executive of Hilton, said.

Hilton has plans to introduce a second brand, which Nassetta has described as a “lifestyle brand,” this fall. Lifestyle hotels often look to borrow special design elements, and replicate them across a brand.

Also last week, Marriott announced that it will add more than 200 high-end hotels to its current lineup of 449 luxury and lifestyle properties. The Bethesda company is investing more than $15 billion for the expansion, which includes adding 23 JW Marriott Hotels & Resorts, 15 Ritz-Carlton properties and nine Renaissance Hotels.

The idea, executives said, is to target millennial travelers, who are expected to account for roughly 60 percent of the company’s business in the next four years.

“We’re looking at a tsunami of next-generation business travelers,” said Catherine Leitner, a spokeswoman for Marriott. “Travelers want a more extensive experience, regardless of their price point.”

Across the industry, hotel companies have made sweeping efforts to attract more millennial travelers. In addition to adding independent and boutique options, hotels are renovating their lobbies to offer more communal spaces, adding WiFi-friendly areas, even expanding their selection of local art and craft beers.

“You’re seeing all of our brands make amendments to attract that next-generation traveler,” Leitner said. “This is a very sizeable demographic.”

Both Marriott and Hilton have been adding hotels at a rapid pace. As of March 31, each company had roughly 200,000 rooms in the works.