This episode is the 100th episode of the series.
This is Marion Ross's second appearance as Richard's cousin Marilyn; the first was at the funeral of Richard's mother Trix, who had also been played by Marion Ross.
Kelly Bishop, although an excellent dancer, asked Edward Hermann to "help her out" while they filmed their first dance on their 40th Anniversary.
Emily mentions that the Sheldrakes were forced to move their retirement party to make room for her vow renewal with Richard. Kelly Bishop, who plays Emily, played Marjorie Houseman in Dirty Dancing (1987). The Sheldrake Hotel featured prominently in that film as the location of Baby's performance with Johnny.
The place where Richard and Emily get married is also the place where Rory went to the dance with Dean and Rory's coming out party.