Preservationists and cruise industry experts are holding panel discussions in downtown Charleston all day today as part of an international conference on the impact the pleasure boat business has on historic port cities across the globe.

Today marks the second day of “Harboring Tourism: A Symposium on Cruise Ships in Historic Port Communities.”

The three-day conference is being held at the Francis Marion Hotel. It was organized by local preservationists, the National Trust for Historic Preservation and the World Monuments Fund to try to help Charleston and other historic port cities balance cruise ship tourism with quality-of-life issues.

Today’s discussions will include panel discussions on topics such as economic impacts and environmental concerns of cruise ships in historic cities.

The growing industry, including its growth in places in Venice, is expected to be a hot topic as the conference resumes today. Venetian architect Paolo Motta is one of the featured speakers. His city saw its annual cruise passenger traffic grow to 2 million in 2011 from 400,000 in 1990.

On Wednesday night, keynote speaker Craig Milan, a former Royal Caribbean executive, told attendees that the largest cruise ships plying the seas, the Oasis class that can carry up to 8,400 passengers and crew and is run by Royal Caribbean Lines, will never call on Charleston.

“I can assure you the Oasis of the Sea will never be in Charleston,” he said. “There’s just not the market for that ship. ... You’ll always be a niche port.”

The conference wraps up by 12:30 p.m. Friday.

Check back at as more updates become available.