NBC has called for a 4th, 5th and 6th season of 'This Is Us', a most popular show for the 18 to 49 year old segmet of the population, and for many others as well. This puts the show in the position to break into the lucrative syndication game once production is done on the show. The network will air 18 episodes per season of the time bending family drama. You'll have to wait until after fall, when the network finishes its annual run of "Sunday Night Football".