Brian Thompson was hired for his role, and then let go without notice before it was filmed. When he sought out a reason why, he was told that he was too large to fit into the costume Christopher Lloyd had worn for Star Trek III: The Search for Spock (1984). He quickly volunteered to make any necessary alterations himself.
Wesley mistakes Ensign Mendon for Mordock, the Benzite that he met in the season 1 Coming of Age (1988). Indeed, both are played by the same actor, John Putch.
Before Riker is transferred to the Klingon ship, Picard says "We know so little about them. There really is so much to learn." In later seasons, Picard would turn out to be an expert on Klingon culture, familiar with their codes of honor and able to pronounce insults in their language.
The Klingon dishes that Riker eats were made of sushi and forms of offal.
First appearance of the Klingon dish gagh.