Bob is a major London legend.Whilst still at the LSE, Elms became deeply involved in the 'club scene' which was developing in London suburbs.[3] He became a columnist for both The Face and NME, writing on both music and fashion.[4] He championed the band Spandau Ballet, having suggested their name, and used to introduce the group at early concerts, performing poetry readings.[4][5] Elms also worked as a DJ at clubs including Palladium in New York.[6] Elms was a chronicler of the New Romantic movement of the early 1980s,[3] which saw him become a popular interview choice for the broadcast media. Elms then developed a broadcasting career of his own, working in both radio and television. He was a contributor to Loose Ends (BBC Radio 4) and presented the Channel 4 travel series Travelog during the 1990s.[7] In 1989 his first novel was published, In Search Of The Crack by Penguin Books.

Elms served as a patron for the Arts Council's Architecture Week until the demise of the event in 2007.[8]

Elms broadcasts a long-running radio show on BBC London 94.9, in 1999 being referred to as "its top presenter".[9] The show features reports, discussions, and call-ins about Greater London, the history, architecture, geography, city planning, language of London, in short, the minutiae of London. Guests who are acknowledged experts in their fields of study appear on a regular basis. An extract of the shows is published as a podcast every week.

Elms is a critic of The Beatles and refuses to play the band on his BBC London daily radio show. He has been quoted: "I just think they are either childlike and simple or rather leaden and pompous – one or the other all the time. For me they turned something that was once sexy and raw and had roots, into something that was totally soulless, playground sing-along music. I think everything that is over-inflated deserves a pin-prick in it occasionally. How can they be above criticism? That's ludicrous."[10]