Developer Don Barden and his two big neighbors, the Steelers and the Pirates, last week finally reached an agreement on traffic issues that have dogged plans for the Majestic Star casino.

It is good news that this stumbling block, which already has delayed groundbreaking for the city's only slots parlor, has been removed, but more work must be done to ensure the project will be a welcome addition to the Allegheny riverbank.

The teams and Mr. Barden agreed on traffic plans and structural improvements, including a pedestrian ramp across Allegheny Avenue from Heinz Field and new signals and controls on the North Side and the West End Circle and Bridge. The state will pick up the largest share of the tab, estimated at $10 million to $16 million. Mr. Barden has agreed to pay up to $1.27 million and the Steelers up to $2 million. The use of public dollars is bound to anger some taxpayers, but they will be the winners in the end, once the casino is operating and paying 54 percent of its revenue to the taxing bodies.

Now the city planning commission can turn to other important elements still on the table for the casino, particularly the massive parking garage that would overshadow the proposed glass and steel structure. A public hearing is scheduled for this month, and we hope Mr. Barden changes the design for the 3,800-space garage.

If he wanted to be a pacesetter, he could do even more. The Pittsburgh Civic Design Coalition, a group of architects and design experts, says Mr. Barden should create a casino that is ahead of its time rather than one that will be obsolete on opening day. He can do that by meeting national standards for green buidings, something he has resisted because green buildings must be either smoke-free or have non-smoking sections with separate ventilation systems.

We agree with the coalition that being smoke-free is an advantage, not a drawback, for a casino. The latest evidence comes from the new Mount Airy casino in the Poconos, which last week announced it was banning smoking on a portion of its casino floor due to customer demand.

Don Barden could make a real impact on the industry -- and Pittsburgh -- by committing to a casino with progressive, sustainable principles. Who says a business that pays off in green can't be built on green?