After Hyuna's departure in July, Yubin was added into the group prior to the release of their debut studio album, The Wonder Years (2007).

[1] The group began their entry into the American market the same year as an opening act for the Jonas Brothers' World Tour, performing English versions of their songs.

In early 2010, Sunmi left the group to pursue an academic career and was replaced by Hyerim prior to the worldwide release of the single "2 Different Tears" later that year.

They performed a cover version of "Don't Cha" by the Pussycat Dolls as well as original songs, including "Irony" and "It's Not Love".

On June 25, Sohee was sidelined for a month after tearing a knee ligament in a fall from a running motorcycle during the filming of the movie I Like It Hot.

[7] The remaining four members continued performing until late July, when Hyuna was withdrew from the group due to her problems with chronic gastroenteritis and fainting spells.

[8] The choreography for the song was simple and widely imitated: by October, many fan performances of the dance circulated on video sharing sites such as YouTube and Daum,[10] including one by a group of policemen who were eventually profiled on SBS's Star King.

[11] The Wonder Girls had an extensive promotional schedule for their album, and in late 2007 they began performing their second single, "이 바보" ("This Fool").

In February 2008, the Wonder Girls joined their producer Park Jin-young for his month-long concert tour through Korea and the United States as special guests, where they filmed the music video for "Wishing on a Star" while in New York.

1 on KBS' Music Bank, staying there for four consecutive weeks,[15] and also won Cyworld's "Song of the Month" award in September and October 2008.

In March 2009, the Wonder Girls confirmed that the group would launch in an English-language music career in the United States with the official release of an English version of "Nobody" in summer 2009.

[33][34] Sunmi continued to work as a participating member of the Wonder Girls in through February in order to complete scheduled events.

[43] On July 30, M.net premiered a new show Made in Wonder Girls that took viewers behind the scenes of the group's first American tour as well as their promotions in Singapore and Indonesia.

On June 30, it was announced on their official website that the girls had been invited to perform at the 2011 Special Olympics closing ceremonies in Athens, Greece.

On August 5, The Wonder Girls appeared on Billboard.com's Mashup Monday program, performing a self-arranged cover version of B.o.B and Bruno Mars' "Nothin' on You".

Promotions for Wonder World began with a comeback stage on Music Bank on November 11 and continued through January 2012.

"The DJ Is Mine", an English-language song featuring School Gyrls, was released as a promotional tie-in single for the movie on January 11.

Following the release of the movie, the group received proposals from major broadcasting companies in the United States, and were in talks concerning full U.S. promotions and activities for their debut English-language album.

[51] The Wonder Girls performed for the last time before their hiatus at the Winter Special Olympics in Pyeong Chang, South Korea on February 5, 2013.

[52] Due to the hiatus, plans for the English-language album, an English television series, as well as any future promotions in the United States were entirely scrapped.

On July 23, 2014, it was announced that Yeeun would be making her debut as solo artist under the pseudonym Ha:tfelt (amalgamation of the pronunciation of the word "Hot" and "Heartfelt").

Rather than solely a dance group, the Wonder Girls returned as a four-member band with each member playing an instrument: Yubin (drums), Yeeun (keyboard), Hyerim (guitar), and Sunmi (bass).

In Korea he created a music video with JY Park, Steven Yuen, the Wonder Girls and Twice, based on Conan's popular "string dance" moves that would become a sort of trademark of his.

On July 5, the Wonder Girls released the song "Why So Lonely", with "To the Beautiful You" and "Sweet & Easy" serving as B-sides, as a CD and as a digital single.

On July 12, the group performed the dance version of Why So Lonely for the first time on SBS MTV's The Show, winning the trophy for that week.

[73] On January 26, 2017, JYP Entertainment announced that Wonder Girls were disbanding, with only Yubin and Hyerim renewing their contracts while Yeeun and Sunmi decided to leave the company.

[3] The Wonder Girls are known as "South Korea's Retro Queens",[2] as their music has been noted to contain elements from the 1960s, such as in their hit "Nobody", 1970s, such as in the reggae track "Why So Lonely", and 1980s, heard on the songs "Tell Me", "So Hot", "2 Different Tears", "Be My Baby" and "I Feel You".

[80] "Tell Me" was voted the number one idol hit of all time in a survey of 22,000 participants conducted by Research Panel Korea in 2013,[81] and was included in Mnet's list of Legend 100 Songs that have captured the public since the 1960s in 2014.

[83] The same publication ranked "Nobody" number 43 in their list of 100 Greatest Girl Group Songs of All Time, deeming its debut on the Billboard Hot 100 "a breakthrough moment in K-pop history".

Shortly after, in the same year, Hyuna left the group due to concerns over her health, which led to the addition of Yubin as replacement.