He then producedBreak Ke Baad(Break ke baad was directed by Danish Aslam) starring Imran Khan and Deepika Padukone in the lead roles. The film is a romantic dramedy and was released in the later half of 2010. His second venture Hum Tum (2004), was one of the biggest hits of 2004 and established him as a director. Hum Tum won five Filmfare awards including Best Director for Kohli. He won against his mentor Yash Chopra who was nominated for Veer-Zaara.
Fanaa, starring Aamir Khan and Kajol who made her comeback after a four-year break from the industry and earned her a Filmfare Best Actress award. It was released in May 2006. Fanaa became one of the biggest hits of 2006. This film was found controversial and was banned in the state of Gujarat due to protests against the lead actor Aamir Khan. Kohli wrote, directed and co-produced the Yash Raj film Thoda Pyaar Thoda Magic, starring Saif Ali Khan, Rani Mukerji, Rishi Kapoor and Amisha Patel. One of his latest projects "Phir Se..." was stuck in controversies involving allegations of plagiarism however the Supreme court had later on allowed the release of the film upon settlement between the parties which made him pay Rs. 25 lacs to Jyoti Kapoor, the plaintiff. Kunal has a three film contracts with Reliance Big Pictures involving financing, distribution and marketing. This contract is estimated to be worth Rs 1.50 billion.
He judged the popular TV show Nach Baliye's second season for Star Plus; the show was a reality dance show and very popular in 2005. He has judged a children's reality show on Sony TV, Chota Packet Bada Dhamaka in 2005. In April 2014, it was reported that he would be the judge in NDTV's talent hunt show Ticket to Bollywood.