Many themes can fit a 50th birthday party. One theme that often comes to mind for a 50th birthday party is the tongue-in-cheek idea of an "over the hill" party. This party theme makes light of the fact that the honored person is getting older.
"Over the hill" parties typically feature props and gag gifts, such as adult diapers and walking canes. They often feature jokes and roasts about the honoree losing his memory. The popularity of this theme has faded over time in favor of more sincere themes.
One way to approach a 50th birthday party with sincerity is to honor the person's life with a "through the years" themed party. With this theme, memories are key; old photos, newspaper articles and guest participation in remembering the past are paramount. Music and slide shows from the honored person's childhood and life can create an atmosphere of happy reminiscence for the party.
A more neutral 50th birthday party theme is to have a "casino night" party. Fill the party space with black tablecloths, red and black balloons and casino-themed decorations. A final touch to this theme is to rent the services of one or several private blackjack or poker dealers.