Musicians will be playing in spots around downtown until 2 a.m. every night through Saturday.
Monday, the Busy Bee Cafe ushered in the first jam session of the festival.
"Always a banjo or two and mandolins and lots of guitars," said jam session organizer David Hedrick.
"Hope the city is excited," said Busy Bee co-owner Woody Lockwood. "I hope to see people out this week supporting it."
"Because it's a lot of fun," said Monty Smith, with the Piedmont Council of Traditional Music. "It's a great genre of music."
Smith says his group is responsible for making sure crowds come out at various bars and restaurants on Fayetteville Street every night this week.
"It will be full of vendors and performance stages," said Smith.
At least 200 vendors, and with an international presence young and old including enthusiasts from Croatia, Japan, Sweden and Germany, to name just a few, expect quality jams.
"That just makes music better taken from other influences and other sources," said local bluegrass enthusiast John Stancil.
Some are estimating as many 80,000 people will head to the events, which means high demand for lodging, food and beverages. That means big bucks for downtown businesses.
"$5 million to the economy of Raleigh after it's all said and done," said Smith. "We're excited a lot of people have been working a lot on this."