Jammin in the Park, a festival celebrating the 50th anniversary of Trinidad and Tobago, was going to be a groundbreaking Caribbean American extravaganza. The country’s ambassador to the United States was set to attend. Beloved Calypso singer the Mighty Sparrow was flying in from the Caribbean to perform, along with local steel-pan drummers and East Indian dancers from New York. There would be vendors selling jerk chicken, plantains and papaya smoothies.

But on that humid August morning in Washington, festival planner Arthur Griffith got a call from the tent vendor — he wouldn’t be able to make it. Griffith needed 20 tents. In five hours.

“I made one call: Robert,” said Griffith, 52. “This was a huge problem. The country only turns 50 once, and we really worried about being humiliated.

“But Robert fixed it.”

Think you’re busy? Meet Robert Jimenez. He’s the go-to organizer for Washington’s year-round roster of ethnic holiday celebrations and festivals — from the Punjabi South Asian Mela in Centreville to the Peruvian Independence Day celebration in Arlington County.

Jimenez is a man obsessed with sound equipment and portable toilets. Here he is on a recent blustery winter morning, all in black, his arms filled with food permits and health code printouts as he leads a group of organizers across a rock-strewn Hyattsville field that will soon be the site of the Latin music festival they’ve dreamed of hosting here for years. He flips open his laptop in the field. “We can have a stage here. The Porta Potties there. It will be the event of the year. We can make it wonderful.”

Like wedding planners, Jimenez wants to create events free of drama and disappointment. And with plenty of parking. Whether it be Korean New Year in McLean or a Salvadoran festival in Hyattsville, he’s preoccupied with potential glitches. “I sleep about three hours a night,” said Jimenez, 45, ordering a triple shot of espresso at a Panera in Silver Spring on a recent morning. “Any number of things can go wrong. The thing is, ethnic festivals have become that particular community’s moment to shine. So the stakes are high.”

Laptop open in front of him, Jimenez was planning the area’s first Dominican festival as well as the also-new Puerto Rican festival. “I multitask festivals and work like three at a time,” he said.

Jimenez, who is compact with buzz-cut black hair, seems to be perpetually opening his laptop or rummaging in his binder for fairground rules, food permits, festival insurance policies, lists of fire-department contacts and maps of parks. He keeps battered folders filled with the endless paperwork that anyone who plans to pull off an event for 10,000 people must file.

“He’s just a very unique hybrid that’s very specific to Washington because we have so many ethnic festivals,” Griffith said. “I’ve never worked with anyone who has crossed so many ethnic groups. I mean, he works with everyone. And to work with them all, at some point, you have to understand them.”

He knows, for instance, that Caribbean music needs a lot of bass vs. Latin music, which requires more midrange levels for horns and percussion. He orders the right speakers and adjusts the sound system before event organizers even ask.

For Washington’s many immigrant populations, ethnic festivals have become an integral part of city life. “For a little while, people can forget all their money problems and family worries and eat food from their country and dance and feel really comfortable. People often find old friends from their home countries who they haven’t seen in years, and they realize that they all live in Washington now,” said Isolina Campos, 74, who has helped organize the Peruvian independence festival for years but recently hired Jimenez because she was overwhelmed with the amount of planning it requires.

Jimenez makes about $5,000 per festival. (He supplements his festival income by working as a international-music promoter.) It’s a price organizers gladly pay after realizing how overwhelming the details can get, said Anteneh Demelash, a community banker who helped plan September’s celebration of Ethiopian New Year at the foot of the Washington Monument.

The festivals are typically funded by donations from wealthy members of the community and by corporate sponsors that want to tap into ethnic markets. But with the high cost of flying in big-name musicians and bills for security and sound systems, some events barely break even. Jimenez says he’s owed money all over town, a statement his clients do not dispute. He puts festival organizers on a payment plan and waits.

Jimenez likes to dish about each community — who always goes over budget, who are the big dreamers and who likes to micromanage.

“You can guess,” he said.

But for every group, the festivals are a source of pride — a taste of the old country and a chance to forget the pressures of their new lives in the United States. “Families will save up and then spend money at these events,” said Rhadames Avila, 54, who organizes Hispanic beauty pageants and is helping to plan the Latin music festival in Hyattsville.

“They are a centerpiece of a family’s year, and Robert is like their problem-fixer.”

Born in the Dominican Republic, Jimenez understands that need to escape, to let the tastes and sounds of the past become present, at least for an afternoon. He moved to this country when he was 12. His mother had five children and worked in a factory making boots for fishermen in New Hampshire.

“I once realized she was so exhausted that she had fallen asleep in the bathroom,” he said. He was in high school at the time and was planning to join the track team. “But I had to quit and help the family by getting a job,” he said.

He worked in housekeeping at a veterans hospital. He worked as a security guard, “so I could study.” He worked as an EMT. “When you come to this country, you have to do every job that will have you,” he said. But his favorite gig was being a DJ at weddings. Hispanic American couples loved the fact that Jimenez was bilingual and knew music from both cultures. “But I would always blow up my equipment,” he said. “The only thing I knew how to do was make it loud!”

He worked his way into the music-promoting world and ended up working for Budweiser promoting the beer at Latino music events and nightclubs in town.

“During that time I noticed Latino musicians coming into the U.S. to perform at ethnic festivals,” he said. “I realized this was a big market that was underserved.”

Gurmit Sunny Malhi, 39, an information technology specialist for the State Department who organizes the Punjabi festival in his free time, met Jimenez by accident when he went to Bull Run Park in Centreville to take the venue’s measurements. He hired Jimenez right away for the South Asian party — but it was 2011, and the event was canceled because of Hurricane Irene.

“Robert stayed through the washout, helping us pack up till midnight and using his contacts to get some money back,” Malhi said. “He’s like this guru of ethnic festivals, period. We hired him again the next year.”

Driving through the Riverdale neighborhood known as Little Mexico after the Hyattsville tour, Jimenez passed a string of Mexican bars, churches and taquerias along with crowds of Mexican workers who were lined up to be picked as day laborers.

“Immigrants work so hard here, and these festivals really matter to them,” said Jimenez, who spent the past few weeks learning how to operate the latest lighting boards and digital consoles. “There’s not a specific college for what I do — ethnic-festival planning. But I patch things together. Like, most immigrants, I’ve done a lot of jobs. But this one has been my favorite. There’s no way I am giving it up now.”