We talk with Chicago Public Library Commissioner Brian Bannon about his vision for bringing the city’s libraries into the 21st century.

The City of Chicago says it now has a greener and more cost-effective way to treat ash trees infested by the destructive Emerald Ash Borer. City crews are inoculating the trees. Officials say the treatment will spare tens of thousands of trees from being cut down, and saves $1,000 per tree in removal costs. We look at how effective the treatment is. Read an article.

Chicago Sun-Times Theater Critic Hedy Weiss joins us to review shows currently on Chicago area stages, including Shrek the Musical at Chicago Shakespeare Theater, Slowgirl at Steppenwolf Theatre Company, and Mojada at Victory Gardens Theater. Learn more about the plays and watch a web extra video review.

In the second mass killing of protesters in three weeks, Egyptian authorities attacked protesters in Cairo Saturday, killing 72. M. Cherif Bassiouni, a war crimes expert and law professor at DePaul University, joins us with insight into the conflict.

New York-based ad firm Omnicom and Paris-based ad firm Publicis merged on Sunday, creating the largest advertising firm with $23 billion in combined revenue. The merger might create complications since it will bring together rival clients, such as Coca-Cola and Pepsi, Procter & Gamble and Johnson & Johnson, and AT&T and Verizon. We have analysis.

Sen. Dick Durbin says the U.S. House of Representatives' bill to cut funding for the Great Lakes Restoration Initiative by 80 percent would severely impact programs created to address ecological problems facing the Great Lakes. Programs to keep Asian carp out of the lakes would be slashed, among others. Elizabeth Brackett has the details. Read a fact sheet.

Author Rebecca Sive joins us to discuss her leadership guide for women, Every Day is Election Day: A Woman's Guide to Winning Any Office, from the PTA to the White House. Read an excerpt.

Chicago artist Leo Segedin, 86, is still painting about his childhood on the west side, and dancing into old age. We revisit Jay Shefsky's profile. View a slideshow of some of Segedin's favorite pieces, handpicked by the artist himself.

We share your thoughts about the fire marshal's proposal to change sprinkler code requirements in Illinois in tonight's Viewer Feedback.

Did Illinois business leaders lobby ratings agencies to lower the state's bond rating? Paris Schutz has the latest details on a bizarre twist in the pension debate.

There’s a battle raging over the Illinois State Fire Marshal’s plan to require all residential and business buildings taller than four stories to be retrofitted with sprinkler systems costing hundreds of millions of dollars. Churches, restaurants, and any building used for gatherings of 50 or more people would also be required to add sprinklers. Opponents say the expense outweighs the fire safety benefits. Eddie Arruza and his guests analyze both sides.

When she was 13, Karsyn Terry took second place in a national, 14-and-under pool tournament. In the 24 years that this tournament has existed, Karsyn is the first African American to make the finals. Now, after a year of intensive training with her father, she is going for first place this weekend. Jay Shefsky has a profile. Read an article.

YouTube personality Emily Graslie, creator of the "The Brain Scoop” channel, joins us to talk about her new gig at the Field Museum as its Chief Curiosity Correspondent. She will also bring some friends from the Field’s collections to share. Watch Emily's online science videos.