Patrick Beresford was first elected to the council in 1982, representing Lancing’s Mash Barn ward before winning a seat for Churchill ward.
The Adur flag at the Shoreham Centre was flown at half-mast last week for Pat, who has been fondly remembered by colleagues.
Council leader Neil Parkin, who was supported by Pat as a policy advisor, paid tribute to his friend.
“I am hugely saddened by the loss of Pat who was a friend as well as a colleague,” he said.
“I send my condolences to Pat’s partner, Joy. Pat was a great servant to Lancing and to the district.
“When you look around at the progress we are making throughout our communities today, with new homes and job opportunities coming here, much of that is built on the foundation of diligence and hard work that Pat put in throughout the years.
“He was a kind and compassionate man who will be missed by us all.”
Pat’s most recent post was as cabinet member for regeneration and he held a passionate interest in developing the district to attract new business and job opportunities for residents.
He piloted through the Adur District Local Plan and initiated projects such as the redevelopment of Adur Civic Centre into affordable homes and the launch of the Shoreham Harbour new homes schemes.
Elected initially as a Liberal Democrat, Pat switched to the Conservative party for his tenure as Churchill ward councillor.
Throughout his time he took a keen interest in planning issues, serving as committee chairman for many years.
With his partner Joy he spent much of his spare time running the Gateway Club in Lancing for adults with learning disabilities. The retired civil servant also loved walking his dog and taking an annual cruise holiday.
Pat’s funeral will take place at Worthing Crematorium on December 2.