The Slug Club

• Type: Elite Student Social Club
• Location: Hogwarts School of Witchcraft and Wizardry (primarily Professor Slughorn's Office and the Hogwarts Express)
• Founder and Leader: Horace Slughorn
• Primary Goal: To build a network of talented, ambitious, or well-connected students for mutual benefit.

The Slug Club is the informal name given to a group of students hand-picked by Potions Master Horace Slughorn. The name is a student-coined term, a pun on Slughorn's surname; Slughorn himself simply refers to the gatherings as small dinner parties or suppers. Membership is by invitation only and is extended to students whom Slughorn believes will become influential, successful, or famous in the future. He selects members based on their magical talent, intelligence, ambition, or, most commonly, their connections to powerful or celebrated individuals in the wizarding world. Slughorn's motivation for creating the club is to “collect” people. He cultivates relationships with these promising students, offering them guidance and using his extensive network to help them in their careers. In return, he basks in their reflected glory and enjoys the perks they send him, such as free Quidditch tickets, boxes of rare sweets, and access to influential circles. There are two known incarnations of the Slug Club. The first existed during Slughorn's initial tenure at Hogwarts and included members like Lily Evans and, most infamously, Tom Riddle. The second version was established in 1996 upon Slughorn's return to teaching, with Harry Potter as its prize member. The meetings typically took the form of lavish parties in Slughorn's office, featuring rich food, drink, and conversation designed to allow Slughorn to assess his students and encourage networking among them.

The Slug Club is a central plot device in Harry Potter and the Half-Blood Prince. Albus Dumbledore explicitly instructs Harry Potter to get close to Horace Slughorn to retrieve a crucial, untampered memory. Harry's forced membership in the Slug Club provides him with the necessary access to his Potions professor. The relationship Harry builds with Slughorn through these meetings is instrumental in his eventual success in obtaining the memory about Voldemort's inquiry into Horcruxes. The club's meetings also serve as important backdrops for character development and key events:

• The first meeting aboard the Hogwarts Express immediately establishes the club's exclusive and somewhat superficial nature, as Slughorn assesses potential members.
• The Christmas Party is a focal point for several subplots: Harry overhears a suspicious conversation between Severus Snape and Draco Malfoy about the Unbreakable Vow; Hermione Granger attends with Cormac McLaggen to provoke Ron Weasley; and Harry's decision to bring Luna Lovegood as his guest demonstrates his loyalty to his friends.
• The existence of the club highlights the themes of ambition and social hierarchy within Hogwarts, creating tension between members and non-members, particularly Ron, who feels excluded and overlooked.

Membership in the Slug Club spans multiple generations of Hogwarts students.

• Tom Riddle: The most infamous member, who used his position in Slughorn's inner circle to gather his first followers, who would become the original Death Eaters. His group included students like Avery and Lestrange.
• Lily Evans: Described by Slughorn as one of his all-time favorite students due to her vivacious personality and exceptional talent in Potions.
• Lucius Malfoy: A member during his time at Hogwarts, though Slughorn did not hold him in as high regard as some others.
• Gwenog Jones: Later became the celebrated Captain of the Holyhead Harpies Quidditch team.
• Dirk Cresswell: Later the Head of the Goblin Liaison Office at the Ministry of Magic.
• Barnabas Cuffe: Later the Editor of the Daily Prophet.
• Ambrosius Flume: Later the proprietor of Honeydukes in Hogsmeade.

• Harry Potter: The star member of the revived club, invited for being “The Chosen One.”
• Hermione Granger: Invited for her outstanding intellect and being a friend of Harry's.
• Ginny Weasley: Earned her invitation after Slughorn witnessed her perform a powerful Bat-Bogey Hex on Zacharias Smith.
• Cormac McLaggen: Invited because of his close relationship with Tiberius Ogden of the Wizengamot.
• Blaise Zabini: Invited due to his mother's reputation as a famously beautiful and wealthy witch.
• Marcus Belby: Invited because his uncle, Damocles, was the inventor of the Wolfsbane Potion.
• Melinda Bobbin: Invited because her family owned a large chain of apothecaries.
• Neville Longbottom: Invited to the initial gathering on the Hogwarts Express but was not selected for full membership, as Slughorn felt his magical abilities did not yet match the reputation of his Auror parents.

• The name “Slug Club” is never used by Horace Slughorn himself and appears to be a nickname created by the wider student body.
• In the film adaptation of Harry Potter and the Half-Blood Prince, some details of the club are altered for narrative efficiency. For instance, Luna Lovegood is depicted as a regular member attending multiple meetings, whereas in the novel she only attends the Christmas party as Harry's guest. (film)