Jennifer Aniston is a Barney's Babe

Jennifer Aniston picks up a few new pieces at Barney’s in Los Angeles on Wednesday afternoon.

The 39-year-old actress will participate in an hour-long “Stand Up To Cancer” telethon, which will air live and commercial-free on ABC, CBS and NBC on Sept. 5. She’ll join Meryl Streep, Forest Whitaker, Lance Armstrong, Charlize Theron, Hilary Swank, America Ferrera, Salma Hayek, Kirsten Dunst, Josh Brolin, Masi Oka and Scarlett Johansson.

During the telethon, viewers will be invited to make donations by calling the celebrity-staffed phone lines or by texting. Musicians and other participants will be be announced soon!

10+ pictures inside of Barney’s babe Jennifer Aniston…