After graduating from the National School of Drama, he did theatre for next four years, until he was offered a role in 'Gandhi' by Richard Attenborough.
Besides acting, as a director he has done over 74 plays and serials, including Mohandas B.A.L.L.B., Wah Bhai Wah, Sahabji Biwiji Ghulamji and Drishtanth, Kanak Di Balli, Albert's Bridge and Panchvan Savaar.
The actor debuted in the silver screen with Shyam Benegal's film 'Arohan' in 1982.
Following that he played the role of Mahatma Gandhi's second secretary, Pyarelal, in the Richard Attenbrough film 'Gandhi' in 1982.
He had acted in a string of art films that came under the parallel cinema category, with leading art films directors, starting with Shyam Benegal's 'Mandi' (1983), Kundan Shah's comedy 'Jaane Bhi Do Yaaro', Saeed Akhtar Mirza satirical 'Mohan Joshi Hazir Ho!' (1984), Mrinal Sen's 'Khandhar' (1984), and Vidhu Vinod Chopra's suspense thriller 'Khamosh' in 1985.
His most acclaimed film roles to date have been that of Dr. Dipankar Roy in 'Ek Doctor Ki Maut' (1991) and Abba ji, (based on Shakespeare's King Duncan) in Vishal Bhardwaj's adaption of Macbeth; 'Maqbool' (2003). Both the films earned him National Film Awards.
Besides films, he was a hit in television also with TV series like 'Karamchand', a comedy television series in the detective genre and then in 'Office Office', a comic satire on prevalent corruption in India.
Last year, Kapoor made his directorial venture 'Mausam' starring his son Shahid Kapoor but the film failed to register success.
Kapoor was recently seen in Vishal Bhardwaj's 'Matru Ki Bijli Ka Mandola'.
The upcoming films of the actor include 'Blood Brothers', 'Awasthi' and 'Happi'.