The sixth season of the American television comedy series How I Met Your Mother premiered on September 20, 2010, and concluded on May 16, 2011, on CBS.

Jennifer Morrison revelead in an interview that she was contracted for 10 episodes but felt that it was likely she would appear in more.

[2] Co-executive producer Craig Thomas said the issue about the identity of Barney's real father was already a plot point in the initial conceptualization of the series.

John Lithgow was the first choice to play Jerome Whittaker and the producers gave him a collection of specific episodes detailing Barney's father issues (including "Showdown") to help him get acquainted with the role.

Thomas said Lithgow will still appear in future episodes, as the role would complicate Barney's connection with Nora.