Chang Youjeong (, born 1976) is a South Korean playwright and director of theater, musicals, and film. Some of her notable works include the musicals Kiss Me Tiger, Finding Mr. Destiny, Oh! While You Were Sleeping, and Brothers Were Brave. Chang has received critical acclaim and awards for her work, including the 12th Korea Musical Awards for Lyrics and Best Work (2006), the 1st Musical Awards for Lyrics and Script (2007), and the 3rd Musical Awards for Lyrics and Script (2009).

She made her debut as film director in 2010 with Finding Mr. Destiny, a movie adaptation of her own hit musical with the same title. Afterward, she directed other films such as The Bros (2017), Honest Candidate (2020), and Honest Candidate 2 (2022).

Early life Chang Youjeong was born in 1976 in Gwangju, South Jeolla Province. She was raised in the countryside of Yeosu by her maternal grandparents. As a child, she learned to play the flute and gayageum. She also studied pansori and won the grand prize for it at the Honam Arts Festival.

Chang's interest in acting was sparked when she attended a church retreat and witnessed a theater performance by college students. This encounter inspired her to join a theater club while studying Korean literature at Korea University. She then studied in England from 1997 to 1998 and spent her part-time money watching musical performances like The Phantom of the Opera and Cats. The following year, she visited India and was inspired by the vibrant dancing and singing in Bollywood movies; this sparked, within her, the idea of combining the solemnity of British works with the popular and comical aspects of Indian works to create a unique performance. At the time, however, she didn't realize she could write it herself.

When Chang returned to South Korea, she saw a program promoting theater and felt drawn to that path. In 2000, she re-enrolled at the Korea National University of Arts to study directing in the Department of Theater. As a student, Chang was a cinephile and additionally had the opportunity to take classes in the film department, located across the hall; there, she met and learned from the director Byun Young-joo. She also took a class on writing musicals taught by American professor Calvin McClinton.

Career Songsan Night Flowers and Kiss Me Tiger During her studies at the Korea National University of Arts, Chang started writing plays. Her debut work as a director was There, Silently, a workshop piece for Yeonwoo Stage. In 2001, Chang began writing The Tiger Maiden is Having an Affair based on "The Tale of Kim Hyeon-gam-ho" from the fifth volume of Samguk Yusa; the tale is about the unrequited love story between a woman, who lives as a tiger by day and a human by night, and an innocent young man named Kim Hyeon. The story, which goes back and forth between the past and the present, is filled with Korean humor.

The performance was first presented in 2002 under the title Songnyeon Yahwa by the theater company Dure. The composition was overseen by musician Kim Hye-seong, and the musical was directed by Son Nam-mok. It was performed at the Munhwa Ilbo Hall from July 4–25, 2002, starring Eom Ki-jun, Chu Jeong-hwa, Kwon Geun-yong, Shin Mun-seong, Jang Geum-jun, Lim Ki-hong, and others. It was performed again the following year at the Daehangno Arunguji Small Theater from April 9 to May 11, 2003. The cast included Song Chang-ui, Han Ae-ri, Kim Hyeon-tae, Lee Ji-won, Kim Na-young, Lee Gil-woo, and Kim Jin-tae.

After graduating from the Korea National University of Arts in 2004, Chang began working in theater and film. While working as an assistant director, she earned less than 5 million won a year. In order to support herself, she also wrote movie scripts. Meanwhile, she wrote a musical script called Finding Kim Jong-wook. She worked tirelessly, often sacrificing sleep; after a year and a half, she returned to the stage.

In 2005, Kang directed the musical Love Quilt which was performed at the Seoul Education and Culture Center Grand Theater from December 16–20. It was created to teach children the value of family; the story follows children and young magicians who want to change their parents but learn to appreciate and cherish them during their adventures. The cast included Bae Moon-joo, Kim Sam-seok, Kang Mi-ri, and others.

In 2006, The Tiger Maiden is Having an Affair was performed under the title Kiss Me Tiger at the Sejong Center for the Performing Arts Small Theater from June 18 to July 6. Also in 2006, Chang acted as director for the musical Lee produced by Seoul Arts Center.

Oh! While You Were Sleeping While recovering from a car accident, Chang stayed home and wrote a musical inspired by her hospital experience where patients required constant care to prevent bedsores. Her volunteering in Eumseong, Chungcheongbuk-do, also influenced the idea. Chang addressed her mental health challenges by offering her services and stayed for a month and a half due to a shortage of volunteers. She then penned the script for a musical called Shall I Dress You Up? as part of her graduation works in 2003. Set in a Catholic charity hospital, the musical revolves around Choi Byung-ho, a spinal paralysis patient who goes missing the night before his scheduled year-end television interview for a local charity program.

In 2005, Shall I Dress You Up? became the first musical production of the Yeonwoo Theater Company; its title was changed to Oh! While You Were Sleeping. Directed by Chang herself, the musical premiered at the Daehakro Yeonwoo Small Theater from December 1, 2005, to January 8, 2006. It features original songs by Kim Hye-sung, who had previously worked with Chang on Songsan Night Flowers. Renowned guitarist Lee Seong-jun was the music director, with choreographer Kim So-yi, stage designer Kim Kyung-hee, lighting designer Sung-Geun Joo, costume designer Ryu Se-jin, sound designer Lee Ji-ho, makeup designer Chae Song-hwa, and stage director Do Hyun-ji.

The production was a huge success, with all 90 seats filled to capacity daily and praise for the vocal performances of Jin Seon-kyu as Choi Byung-ho, Lee Sang-eun as Doctor Lee, and versatility of Jeon Byeong-wook as Peter in blending serious and comedic elements. The production also won the Writer Award and the Best Musical Award at the 12th Korea Musical Awards. Additionally, the production won the Best Work Award and the Scriptwriter Award for Chang at the 12th Korea Musical Awards. It was also nominated for the Best Re-Performance Award at the 1st Musical Awards. After the premiere's success, offers for Chang poured in: "It was so scary... because I had just gotten the flicker of a 200-seat stage and I woke up to this overwhelming amount of promise and expectation. Everyone waits for an opportunity to come along, but I knew that if I grabbed for anything more than that, my inadequacies would be exposed."

The musical continued running at the Daehangno Art Theater Tree and Water from September 2006 to July 2007. New actors Kim Ji-sung, Kim Jae-beom, Kim Moon-sung, Kim Ji-sun, and Oh Yoon-joo joined the cast with Jeon Byeong-wook and Yoo Ha-na, who had appeared in the 2005 premiere.

In 2007, the fourth season of the show ran from January 6 to July 22 at the Daehakro Arts Center Hall 4. The cast included Jeong Ui-wook and Park Hoon as Father Peter, Kim Moon-seong and Ahn Se-ho as Choi Byung-ho, Park Bo-kyung and Lee Jin-hee as Choi Min-hee, Yoo Ha-na and Kim Na-jung as Kim Jung-yeon, Kim Jae-beom and Seong Du-seop as Doctor Lee, Kim Ji-seong and Kim Jin-hee as Lee Gil-rye, and Park So-young as Jeong Sook-ja. In 2008, the fifth season began on July 25 at Le Meilleur Theater and concluded on October 26. Since 2016, Lee Ji-yeon took over as director.

Melodrama While writing the foundation for Finding Kim Jong-wook that was developed from 2002, Chang wrote a play script titled Melodrama. It became the third work of Ida's Stage Discovery Series organized by Ida Entertainment in 2007. The play centers around five characters: Kim Chan-il and Kang Seo-kyung, who have been married for 10 years; and siblings Park Mi-hyeon and Park Jae-hyun, along with their friend Ahn So-yi. The siblings and Ahn So-yi were involved in a car accident in their youth, resulting in the loss of their parents and Ahn So-yi's brother; Mi-hyeon suffered a loss of intelligence, while Jae-hyun received a heart transplant from Ahn So-yi's deceased brother. Following the accident, Jae-hyun becomes engaged to Ahn So-yi, and it turns into chaos after Kang Seo-kyung has an affair with Park Jae-hyun while Kim Chan-il has an affair with Park Mi-hyeon.

With Chang as director, Melodrama was first performed at Daehangno Cultural Space Ida 2nd Theater from September 9 to November 4, 2007. The cast included Jo Han-chul, Chang Young-nam, Kim Ji-seong, Lee Shin-seong, Lee Jin-hee, and Park So-young. It was subsequently extended from November 8 to December 31 that year. Later, the play won of the 2008 Dong-A Theater Award, after which it was re-performed at Daehangno Cultural Space Ida 2 from September 5 to November 2, 2008. Kim Sung-ryung joined the original cast, replacing Chang Young-nam as Yoo-kyung; Kim Jin-hee and Jeong Dong-hyun replaced Lee Shin-seong.

In January 2015, Melodrama returned for the first time in 6 years. This stage was co-organized by Seoul Arts Center (President Hak-chan Ko) and Ida Entertainment. Running until February 15, it was produced by Sang-won and held at the Seoul Arts Center Free Small Theater in Nambuhwan-ro, Seocho District, Seoul. It starred Park Won-sang and Choi Dae-hoon as Chan-il, Bae Hae-sun and Hong Eun-hee as Seo-kyung, Park Sung-hoon and Jo Kang-hyun as Jae-hyeon, Kim Na-mi and Park Min-jung as So-yi, and Jeon Kyung-soo as Mi-hyeon.

Finding Mr. Destiny Inspired by a drunk man at Dolgoji Station in Seoul in 2002, Chang wrote the hit musical Finding Kim Jong-wook. She had gone to India three times for further research to develop the story and characters. While the plot and characters were finalized, Chang needed to rationalize why the protagonist, Ji-woo, didn't search for her first love, Kim Jong-wook, despite having his resident registration card; once she resolved this issue, however, she completed the script in just three days. This musical became her first full-fledged directing work.

The musical began as a university performance directed by herself and composed by fellow student Kim Hye-seong. The production, which had a budget of ₩100,000 (US$87.31), starred Kim Ji-hyun as the female lead, Jeon Byeong-wook as Kim Jong-wook, and Min Jun-ho in multiple roles; it was performed as a graduation performance at the Black Box Theater of Korea National University of Arts. The performance was well received by their professors, leading to an official invitation to the 15th Istropolitana Project, an international student theater festival held in Bratislava, Slovakia from June 26 to 30, 2004. In December of that year, Dolgochi, the theater club of the university, performed the musical at Jayu Small Theater for three days as an incubator performance with Kim Ji-hyun reprising her role.Dolgot-yi An encore performance took place in the same venue in February 2005. The incubator performance was selected as the best work at CJ Entertainment's Musical Showcase, after which CJ Entertainment acquired the performance rights in 2004 and collaborated with Musical Haven for the joint production.