[6] Although he initially announced retirement upon disbanding the group in 1996, Taiji released his first solo album two years later and continued his successful career.

He took the stage name of "Seo Taiji" at age 17, when he was recruited into the heavy metal band Sinawe as bass guitarist by Shin Daechul.

Although also including Yang Hyun-suk and Lee Juno, Taiji was the leader and main songwriter and began his signature of mixing many different genres of music.

They had several controversies with songs and lyrics, but became the first modern highly successful band in the South Korean music industry.

There was some controversy over his sudden reversal of retirement, but his first Solo album Seo Tai Ji sold more than a million copies, even without any promotion in Korea.

However, unlike Ultramania, 7th Issue was recorded mostly on a dropped C tuning, which gave the effect of the album sounding like one long song.

Also, he obviously added Drum and Bass sound into his several songs, so that it proved him to be a favorable electronica musician (skills he learned from producing the "Seo Taiji and Boys" albums).

"Robot" deals with his youth and anguish, while the song "F.M.Business" acrimoniously criticize the issues of and the commercialized music business and the artist exploitation from greedy corporate record labels.

Seo returned to South Korea after a long absence, and revealed his latest single "Moai".

In his single "Moai", Taiji reinvents his sound, and introduces a new experimental style he calls "nature pound".

He performed at the 2008 ETPFEST which he spearheaded to promote his comeback alongside bands such as The Used, Dragon Ash, Death Cab for Cutie and Marilyn Manson.

Seo also put together "The Great Seotaiji Symphony" with Tolga Kashif and the Royal Philharmonic Orchestra to perform his old hits and new songs presented in an entirely new form, combining rock and classical music.

[10] Seo's 15th anniversary album consisted of most of his works so far,[11] re-recorded and re-mastered but it was released in a limited edition with only 15,000 copies available, each with unique serial numbers.

[17] The first single from this project, a cover of "Come Back Home" (from Seo Taiji and Boys IV) recorded by BTS, was released with a music video on July 5, 2017.

On April 21, 2011, Sports Seoul broke the story (later confirmed by numerous media outlets) that Seo Taiji had secretly married actress Lee Ji-ah (real name Kim Sang-eun) from October 12, 1997, until August 9, 2006.

[23][24] In January 2011, Lee sued Seo for ₩5 billion of her share of matrimonial properties and ₩500 million in alimony, and court papers caused their relationship to go public in April.

[27][28][29] In August 2014, Seo released a statement denying several of Lee's claims about their marriage when she made a guest appearance on the talk show Healing Camp, Aren't You Happy.

[33][34][35][36] They met in 2008 when Lee appeared in the music video for "Bermuda Triangle" (on Seo's eighth album), and began dating in late 2009.

[41][42] Although Taiji now works as a "solo" artist, the following musicians consistently play with him during tours, studio recordings, and music videos.