Today’s announcement that morning-news hot shot Chris Licht will become showrunner for Stephen Colbert’s topical late-night comedy show is the result of conversations that started around the time of Colbert’s post-Super Bowl broadcast.

At the heart of those conversations between CBS Corp. CEO Leslie Moonves and Late Show Cobert LogoColbert and also between Colbert and CBS Entertainment chief Glenn Gellar: the need for a showrunner. The very hands-on Colbert, who’d formerly put out a half-hour show, four days a week, from an intimate West Side studio for Comedy Central, now is handling a five-day-a-week, hourlong program for CBS from the cavernous Ed Sullivan Theater. General consensus at CBS: Colbert needed someone who could wrangle the enormous daily undertaking, and make the train run on time.

“They did a Herculean job launching the show with the core team that did The Colbert Report. But once the rubber hits the road on a daily basis, they need a showrunner … who can provide the operational system that supports Stephen,” prognosticated one industry pundit.

Enter Licht, an ambitious, highly regarded news exec who had Chris Lichtspent the past several years turning around CBS News’ morning show, after launching Morning Joe for MSNBC. It was the worst-kept secret in TV news that Licht was mulling what to do next, after delivering the morning program’s biggest numbers in more than two decades.

“He’s really skilled operationally and he knows how to produce a daily show, which is exhausting,” one industry watcher said. “Licht does two hours live every morning. The ability to bring in Chris to partner with Stephen will provide a much better support structure around him.”

About four weeks ago, CBS News chief David Rhodes met with Moonves, at which Licht came up. Moonves suggested moving him to The Late Show, sources say.

Licht and Colbert met for the first time on the subject last week. Licht will oversee all aspects of production for The Late Show.

Licht’s appointment does not impact Tom Purcell, who’s described as Colbert’s head of creative, or Meredith Bennett, who oversees business and production functions. Today’s announcement from CBS listed both as EPs on the show, as are Colbert and Jon Stewart.  Stewart has had an EP role on the show since he launched it, literally, dressed up as an umpire shouting “Play ball!” in the premiere episode.

But morning news and late-night TV are different beasts, industry watchers note. That said, the median age of Colbert’s CBS late-night show is 58.2 years; the median age of the morning news program Licht is leaving to head to Colbert’s show: 61.1. Similarly, NBC’s The Tonight Show Starring Jimmy Fallon has a median age of 55.1 years, and Today‘s is 57.4. ABC’s Jimmy Kimmel Live is 57.2, and its Good Morning America is 59.2.

Season to date, Late Show is averaging 2.9M viewers and 859K viewers in the 18-49 age bracket. Colbert trails Fallon’s show (3.4M,1.3M) but bests Kimmel (2.4M, 715K).

But, during most recent weeks, Colbert is getting results more in line with what his predecessor David Letterman was doing a year ago. Averages for the first quarter of this year show Colbert still up substantially, year to year, compared with Letterman in the demo, but by a lot less than in his in full season-to-date comparisons. And the total viewers average is slipping into Letterman territory in the first quarter.