Strongly influenced by reading Nikolaus Pevsner's The Buildings of England, architectural review of the country, Grundy has taught at north-east schools since 1970.

In the late 1980s he worked for the Historic Buildings and Monuments Commission before beginning a more widely-recognised career as an architecture writer and television presenter, especially in the north of England. He is currently a lecturer of English Literature at South Tyneside College.

John Grundy does live documentaries aboard the Shields Ferry, which cruises up and down the Tyne from South Shields to Newcastle upon Tyne.

In the late 1990s Grundy co-wrote/edited the new edition of Niklaus Pevsner's Northumberland, part of Pevsner's Buildings of England series.

Steve Robins, who produced all of Grundy's TV programmes from 1999, left Tyne Tees Television in 2005 and founded the production company Working Wonders TV which produced the last series of Grundy's Wonders, and Grundy's Northern Pride.

Grundy Goes... (1996—1999) broadcast on Tyne Tees partly involved Grundy becoming the interesting historical characters found in the histories of the buildings he visited.

Townscape was on BBC One North East & Cumbria. Grundy's Wonders another, longer-running Tyne Tees series, Grundy explored architecture in the north-east, as well as Cumbria and Yorkshire. Grundy's Northern Pride has been broadcast since 2007 in the Tyne Tees and Granada Television regions and covers the same area as Grundy's Wonders plus North West England.

Travels with Pevsner is a BBC Four series that involved Grundy visiting places visited by Nikolaus Pevsner during his ambitious review of English architecture in the 1950s and 1960s.