After taking a first in Arabic at Cambridge University in 1969, Jim worked in book publishing in London in the early 70s and moved to Beirut in January 1975. He covered all phases of the Lebanese Civil War 1975–1990 for the BBC and many other radio and print outlets. He then moved to Bosnia in the early 1990s before arriving in Cairo as BBC Middle East correspondent in 1995. Jim then reopened the BBC Tehran bureau and was correspondent there from 1999 to 2004.
In 2005, he returned to Beirut and spent much time covering Iraq for the BBC, followed by the overthrow of Mubarak in Egypt in 2011. Jim also provided a large proportion of the BBC's coverage of the Syrian uprising and civil war from the spring of 2011. Since 2016, he has taken a lengthy sabbatical from the BBC. He was a Visiting Fellow at the Middle East Centre from 2018–19.