But this year is different, reports CBS News correspondent Russ Mitchell. This year it's Rosie Donaghey.
"Why should I be picked to be given such a big honor?" Rosie asked.
She was born Rose McElroy 88 years ago in County Tyrone, Ireland. She and her husband James Donaghey came to America in 1949 with a 6-month-old baby in tow - like so many immigrants, looking for work.
"I started the day after I landed here and I'm 60 years here," Rosie said.
For a half century, with some time off to raise her family, Rosie has worked as a waitress all over New York - from a Manhattan tea room to a Jewish delicatessen. And for the last 20 years, she has worked in the Bronx.
"I always tease when she says 'this is my boss', and I say, 'No, she's my boss'," says Kathy Gallagher, manager of the Wicked Wolf.
Gallagher, who first hired her 14 years ago, says Rosie is part of the attraction for some customers.
"She has her regulars come in," Gallagher says. "She loves to meet and greet them and sit with them."
"I've known her for 40 years," says one customer. "She's a great waitress. We haven't been here in a while and she still remembers what everybody drinks."
All that makes Rosie a great worker. But it doesn't explain her special place in the neighborhood - or why she was chosen for today's honor.
Why was Rose picked to be grand marshal?
"People have asked me that, 'what has she done?'" Gallagher says. "One story comes to mind, I got a call from a friend in Florida who knew her years ago and when he found out she was grand marshal he said, 'when my family years ago didn't have anything she would come into my household and just make sure we always had something to eat.' And he said life was tough back then but she was kind always the quiet person behind the scenes to make sure everyone was ok."
So this St. Patrick's day, don't forget a tip of the glass to one of Ireland's best, Rosie Donaghey.
"Is it too early for an Irish whiskey?" Mitchell asks.
"Oh for you yes!" Rosie replies. "You have to go back to work."