The lunchtime drama that played out Wednesday in downtown Baltimore offered fresh evidence that the city needs to get its act together regarding food trucks.

Irene Smith had parked her Souper Freak truck at the corner of Calvert and Monument to sell soup and sandwiches, as she had for several prior Wednesdays, when a city official told her she was in violation of the law and should shut down. A steady stream of customers were told this could be the last Wednesday they could spoon down $4 cups of spicy fish soup. Earlier in the day another food truck, IcedGems Baking, parked near the same spot and was told it could not sell cupcakes and ordered to leave. Food trucks working other areas of the city reported no such problems.

At issue on Calvert Street was a city regulation that prohibits a vehicle selling food for immediate consumption from parking within 300 feet of any retail business establishment that sells similar food products. The food truck operators contend their fare is different than what is sold nearby, but moreover that the city's permitting process is confusing and expensive.

It costs close to $500 to acquire a mobile food vendor's license in the city, while another agency, one in charge of enforcing the 300-foot rule, issues a separate $25 street vendor license, which Ms. Smith was told she needed. To get one, she will have to appear before a commission that won't meet until June but might not be able to get on its agenda until August. Meanwhile, another truck that serves hamburgers and frequents the same Calvert Street spot on Thursdays has been told it doesn't need a street vendor license.

Lunch should not be this confusing, or this tense. What is needed a coherent structure to work out the potential conflicts between proprietors of brick and mortar restaurants, who are worried about losing their customers, and food truck operators, who are bringing vitality and culinary diversity to city streets.

Compared to other cities, Baltimore does not have many food trucks, mobile kitchens that roam the streets sending out daily messages on Facebook and Twitter describing their menu items and parking spots. Right now the tally is about half a dozen, though the city has achieved that number in a little over a year. This pales compared with the 200 in Portland Oregon and the dozens in Washington. D.C. But the number in Baltimore is likely to grow as the old sit-down middle of the day style of eating gives way to a grab and go approach.

While food trucks are generally welcomed by consumers, their presence does generate some complaints from nearby businesses and would-be parkers. As The Sun's Jill Rosen reported this week, food truck operators are often treated like vagrants, regularly urged by authorities to move along.

This is unfortunate. Proprietors of food trucks have to pass the same health inspections that traditional restaurants do. Acquiring the stack of permits, licenses and certifications needed to operate a food truck in Baltimore City requires visits to multiple agencies and can cost close to $1,000, the operators report. Even then, as the Calvert Street episode shows, there can be legal tangles.

A big issue with food trucks is where they park. They can't be too close to competitors but have to be near customers. Some spaces, such as those near the Johns Hopkins and University of Maryland medical campuses, are so prized that food truck operators wheel in at 6 a.m. just to secure a space,

This ad hoc system needs more structure. One solution worth considering, proposed by Ms. Smith, would be to get the city to set aside spaces like it does for Zip Cars. Food truck operators, working with the city officials, could designate 10 or 12 areas around the city for food trucks. These spots could be set in food dead zones, those without restaurants selling similar fare. Truck operators would have to pay another fee to acquire a permit that allowed them to park there, but they would be guaranteed a spot on a certain day of the week.

The city needs an advisory group composed of food truck operators and city officials overseeing parking and zoning regulations. The group could also examine the city permitting process, eliminating contradictions, streamlining areas of jurisdiction and making clear exactly what operators need to be legit.

Food trucks bring a lot more to a city than tasty food. They can improve the street life, encourage people to explore different neighborhoods and cuisines, and add a zest to urban living. They too have to play by the rules, but those that do should be encouraged, not hassled.