Made obvious in several scenes in this episode (and Virtuoso (2000), for that matter), Robert Picardo, the Doctor, is an accomplished singer. While he was at Yale University, he was a member of the Society of Orpheus and Bacchus, the second longest running undergraduate a Capella group in the United States. Then in 1977, he made his Broadway debut. He appeared in Gemini (1977) and Tribute (1980).
Dr. McCoy's famous phrase from Star Trek (1966), "I am a doctor, not a _____" is referenced when the holographic version of Dr. Zimmerman states, "I am a diagnostic tool, not an engineer!"
The Swarm species are the first Delta Quadrant species encountered by Voyager to possess transporter technology.
Along with Unity (1997), this is one of only two episodes in which the title card appears in the upper right hand corner rather than the left.