Jun. 21--While an OK from government regulators remains months off and union pilots still need to resolve dicey seniority issues, the heavy lifting involved in integrating Northwest Airlines and Delta Air Lines is under way.

In a message to employees this week, the Northwest and Delta CEOs said 25 integration teams are in place, made up of 300 leaders from both airlines. The teams are working on such things as coordinating ticketing and frequent-flier programs and making sure airline employees who work with customers are wearing the same uniforms "as soon as possible" after the deal closes.

Behind it all are important financial goals the airlines have promised Wall Street. One mission of the 25 teams is to find the more than $1 billion in cost savings and revenue-generating "synergies" touted by airline executives.

The Thursday memo from Delta's Richard Anderson and Northwest CEO Doug Steenland says that on Day 1 after the merger closes, they aim to have the same uniforms for employees, a reciprocal code-sharing system for booking flights on the now-single airline and a similar set-up for the frequent-flier programs.

Also, early next month, the airlines plan to announce the executive team that will run the combined carrier once the merger closes. The deal still needs antitrust approval from the U.S. Department of Justice, which isn't expected until late this year.

The new airline will be called Delta and have its headquarters in Atlanta, effectively erasing