Coco Whittaker of the Twentieth Century Society will be delivering a talk organised by Shrewsbury Civic Society. The event, focussed on Shropshire Council's headquarters, will take place at 6.30pm at Bear Steps on Wednesday, June 14.
The society is campaigning to save Shirehall, which faces being sold off for development land under council plans.
Shropshire Council wants to leave Shirehall for new premises, which could be part of the redevelopment of Shrewsbury's Riverside.
The council had been looking for temporary premises to leave Shirehall until the new site was built, but last summer confirmed it had abandoned those plans and would remain at the building until its fresh base was completed.
Shirehall has never come back into full use since the pandemic, with some of the upper floors not being occupied by staff.
Ms Whittaker has been the Twentieth Century Society's caseworker on efforts to save Shirehall – which have included objecting to a 'Certificate of Immunity', which prevents the building being granted listed status – a designation which would have prevented its demolition.
Speaking ahead of the talk she said: "One high-profile case I’ve worked on is The Shirehall, the headquarters of the Shropshire Council, which was built in the 1960s to designs by the county architect Ralph Vernon Crowe.
"Described by Nikolaus Pevsner in his guide to Shropshire’s buildings as 'The major monument to post-war modernism in the county', The Shirehall stands in the county town of Shrewsbury where, it so happens, I was born."
She added: "It would be a huge shame if The Shirehall is bulldozed, and its loss would be felt not only by Salopians but by people all over the country.”
Tickets for the talk are available at eventbrite.co.uk/e/the-20th-century-society-post-war-civic-buildings-plus-saving-shirehall-tickets-627445455247