The Big Bang Theory is here to stay ... for at least three more years. Show network CBS has made a massive renewal pact with Warner Bros. TV that will extend the series for at least three more seasons. The Big Bang Theory is in its seventh season, and current episodes have garnered the series' highest ratings to date. The show is the number-one comedy that airs on primetime television. "Comedy is a big part of our schedule, and The Big Bang Theory is the biggest comedy force on television," CBS Entertainment chairman Nina Tassler stated. "This muti-year deal further strengthens our network's position for future seasons and marks another chapter in the great partnership CBS enjoys with Warner Bros. Television." Contract renewal negotiations with show stars Jim Parsons (Sheldon), Johnny Galecki (Leonard), and Kaley Cuoco-Sweeting (Penny) are currently in progress. The Big Bang Theory first aired in 2007. The show follows physicist roommates Leonard and Sheldon, along with Penny, a waitress and actress who lives down the hall. The show often contrasts Penny's social skills and common sense with the boys' social awkwardness for comedic effect. The show's seventh season is currently in progress, and airs at 8 p.m. ET on Thursdays.