By Steve Tawa

PHILADELPHIA (CBS)–Look out, the law is in town. Top brass from around the country are attending the International Association of Chiefs of Police Conference at the Pennsylvania Convention Center.

Philadelphia Police Commissioner Charles Ramsey delivers the opening address by giving his views on policing in the 21st century, according to IACP Executive Director Bart Johnson.

“He’s going to talk about leadership in a big city, and speak extensively about his experiences during many decades in law enforcement.”

Attorney General Eric Holder and FBI Director James Comey are the featured attractions on Monday.

On Tuesday, outgoing Boston Police Commissioner, Edward Davis will provide insights into the multi-agency response to the Boston Marathon Bombings.

Along with the Mayor and Governor, Davis ordered a daylong, city-wide lockdown after the two suspects were involved in a shootout with police.

In addition to speakers, forums and technical workshops, 750 exhibitors will be displaying a wide range of products and services, including uniforms, weaponry and other equipment.

The five day conference is expected to attract 13,500 people. The Philadelphia Convention and Visitors Bureau estimates it will have a more than $39-million economic impact.