Southern Dallas County is finally beginning to develop after years of watching communities to the north enjoy the economic benefits of a building boom.

But the biggest challenge in the southern sector may be getting everyone to agree on how to handle the development.

Commissioner John Wiley Price has led a regional effort to devise a master plan for the trade corridor in his district that runs along Interstate 45. Mr. Price said the area needs to attract high-quality development with adequate infrastructure that will provide the most jobs and biggest increase to the tax base.

But some developers object to the plan, saying it will add unnecessary delays and uncertainty as well as another layer of bureaucracy that will scare off investors with new regulations. The Allen Group, which owns 6,000 acres, is one of several developers who said they were left out of the planning process.

Next month, commissioners will vote on whether to pull out of the planning process. At least two commissioners, Kenneth Mayfield and Maurine Dickey, expressed concerns Tuesday about how it has been handled.

"There are too many questions that need to be answered," Mr. Mayfield said.

Ms. Dickey said: "We need to start all over. This is a skewed process."

The county's proposed comprehensive plan would identify the infrastructure needs, such as water, sewer and roads, and provide a framework for building them.

The North Central Texas Council of Governments, the city of Dallas and the county are each expected to chip in $290,000 for the plan, which is expected to be competed by April 2010.

Artis Johnson, the mayor of Hutchins, asked commissioners not to be a part of it.

Tiny Lange, a Wilmer council member, told commissioners that her city feels the county is trying to tell officials how to run their city.

Richard Allen, chief executive of the Allen Group, told commissioners that his company has spent the past three years and millions of dollars getting various development approvals from the two cities as well as others.

Mr. Allen's company is helping develop an area known as an inland port because of a Union Pacific rail terminal that moves overseas shipping containers by truck and train across the country.

The intermodal rail terminal has begun attracting warehouses, distribution centers and industrial parks.

Mr. Allen said he has "grave concerns" about a new governmental entity that might be formed to impose restrictions on development, such as new taxes.

"Essentially, we're doing over everything that's been done," he said about the master plan. No one will invest in the area, Mr. Allen said, if they "don't know what the rules are."

Mr. Price bristled at the criticism, telling one developer sarcastically, "We're glad you finally got there," referring to southern Dallas County.

Not all developers oppose the county's participation in the planning process.

Mike Rader, a landowner and developer who helped bring Union Pacific to the area, said the trade corridor needs $200 million worth of basic infrastructure such as water, sewer and roads in order to attract development.

He said Wilmer cannot handle the development, and he encouraged commissioners to continue their efforts so that 25,000 acres along I-45 can get basic infrastructure.

Rick Loessberg, the county's director of planning and development, said the comprehensive plan will not supersede local zoning regulations or result in a new governmental entity. He blamed the recent dustup on miscommunication.

Mr. Price noted that about a third of the area in question lies in unincorporated Dallas County. And, he said, the developers are using scare tactics and conspiracy theories to derail the plan.

He called it "planning 101."

In other business on Tuesday, commissioners voted 3-2 not to seek an attorney general's opinion on whether District Attorney Craig Watkins created a conflict by representing Sheriff Lupe Valdez in a legal fight against the commissioners.

Mr. Watkins' office represents commissioners in legal matters, but he sided with the sheriff in a legal fight he lost over allowing jail access to a documentary film crew.

Commissioners Dickey and Mayfield voted for the AG opinion.

Dallas County Commissioners approved a new budget Tuesday for the 2008-09 fiscal year that begins Oct. 1.

HIGHLIGHTS:

•General fund: $512.7 million

•Increase over current year: 2.4 percent

•New positions: 39

•Deleted positions: 87

•Frozen positions: 53

•Salary increases: none

•Tax rate: 22.81 cents per $100 of valuation. The owner of a $182,000 home, the Dallas County average, will pay $415 in county taxes.