Organizers have been planning this afternoon's rush-hour shutdown of Century Boulevard near LAX for months. The script, so to speak, calls for 400 arrests during the demonstration by workers at LAX hotels and their supporters.

The Los Angeles Police Department has been involved at nearly every stage, advising organizers on how to proceed without endangering public safety. Experts say the close cooperation with law enforcement reflects a more powerful and mature labor movement, and a city government that is far friendlier to labor than its predecessors.

Organizers obtained a permit this week for 1,000 to 2,000 marchers. About 400 of them have signed forms pledging to be arrested and have taken a mandatory class that taught them how to remain calm even when screamed at or insulted.

The driver's license numbers and other personal information of those volunteer arrestees have already been passed on to the LAPD to expedite processing. (Police sent word that six of the volunteers should rethink their participation; though no official reason was given, the six may have outstanding warrants, union officials said).

Parking has been arranged for the arrestees.