Cady Heron wordt opgenomen bij de populairste meiden, de Plastics, van haar nieuwe school waar ze, na haar hele leven in Afrika te hebben gewoond, naar toe gaat. Totdat ze verliefd wordt op het ex-vriendje van de leidster van het groepje, Regina George. Regina papt het, terwijl ze zegt een goed woordje te doen voor Cady, weer aan met Aaron en kust hem voor haar ogen.
| Sound | Rolfe Kent | Original Music Composer |
| Camera | Daryn Okada | Director of Photography |
| Production | Lorne Michaels | Producer |
| Directing | Mark Waters | Director |
| Writing | Tina Fey | Screenplay |
| Editing | Wendy Greene Bricmont | Editor |
| Costume & Make-Up | Mario Cacioppo | Makeup Artist |
| Costume & Make-Up | Jo-Ann MacNeil | Makeup Artist |
| Visual Effects | Bryan Hirota | Visual Effects Supervisor |
| Art | Danielle Fleury | Set Dresser |
| Visual Effects | Kim Boyle | Visual Effects Producer |
| Production | Marci Liroff | Casting |
| Production | Louise Rosner-Meyer | Co-Producer |
| Art | Cary White | Production Design |
| Sound | Amanda Scheer-Demme | Music Supervisor |
| Production | Jill Messick | Executive Producer |
| Costume & Make-Up | Mary Jane Fort | Costume Design |
| Sound | Buck Damon | Music Supervisor |
| Directing | Joanne T. Harwood | Script Supervisor |
| Sound | Beth Sterner | Supervising Sound Editor |
| Art | Patricia Cuccia | Set Decoration |
| Sound | Nick South | Music Editor |
| Sound | Marc Fishman | Sound Re-Recording Mixer |
| Production | Louise Rosner-Meyer | Unit Production Manager |
| Crew | John Stoneham Jr. | Stunt Coordinator |
| Sound | Jim Harrison | Music Editor |
| Sound | Patrick Cyccone Jr. | Sound Re-Recording Mixer |
| Sound | Chuck Michael | Supervising Sound Editor |
| Production | Marie-Claude Harnois | Production Coordinator |
| Editing | Dana E. Glauberman | Additional Editing |
| Camera | Angelo Colavecchia | Camera Operator |
| Art | Collingwood Brown | Art Department Coordinator |
| Art | Brandt Gordon | Art Direction |
| Camera | Angelo Colavecchia | Steadicam Operator |
| Production | James Powers | Production Manager |
| Production | Jennifer Guinier | Associate Producer |
| Costume & Make-Up | Lindsay Jacobs | Costume Supervisor |
| Camera | Michael Gibson | Still Photographer |
| Editing | Kris Cole | Assistant Editor |
| Costume & Make-Up | Luis Sequeira | Assistant Costume Designer |
| Sound | Bruce Carwardine | Sound Mixer |
| Sound | Frank Smathers | Dialogue Editor |
| Sound | Mike Szakmeister | Supervising Dialogue Editor |
| Sound | Susan Kurtz | Dialogue Editor |
| Sound | Christopher Sidor | Sound Recordist |
| Writing | Rosalind Wiseman | Book |
| Crew | Angelique Lewis | Stunts |
| Directing | Joel Hay | Third Assistant Director |
| Production | Jordana Lieberman | Production Assistant |
| Lighting | Bob Hannah | Electrician |
| Editing | Saul Saladow | Assistant Editor |
| Production | Vince Nyuli | Location Manager |
| Editing | Eric O. Schusterman | Assistant Editor |
| Art | David Jaquest | Set Dresser |
| Crew | Rob Sanderson | Special Effects Coordinator |
| Crew | Bryan J. Thomas | Stunts |
| Lighting | Jim MacCammon | Electrician |
| Production | Raquel Rose | Production Assistant |
| Production | Alex Makrygiannis | Assistant Location Manager |
| Costume & Make-Up | Christina Cattle | Costumer |
| Crew | Karen Pidgurski | Unit Publicist |
| Sound | Julie Feiner | ADR Editor |
| Production | Danis Goulet | Casting Associate |
| Sound | Jeremy Pitts | Foley Editor |
| Sound | Sarah Monat | Foley Artist |
| Production | Susan Shopmaker | Casting |
| Camera | Mark Cyre | First Assistant Camera |
| Camera | Andy Jekabsons | First Assistant "B" Camera |
| Lighting | Howard Galbraith | Assistant Chief Lighting Technician |
| Sound | Markus Wade | Boom Operator |
| Camera | Neil Trafford | Second Assistant Camera |
| Camera | Cylvan Desrouleaux | Second Assistant "B" Camera |
| Directing | Sarah Campbell | Second Assistant Director |
| Lighting | Gary Deneault | Electrician |
| Production | Gerrod Shully | Production Assistant |
| Camera | Robert Vigus | Grip |
| Camera | Sean Bourdeau | Second Company Grip |
| Production | Jamie Sparer Roberts | Casting Associate |
| Art | Vic Rigler | Property Master |
| Costume & Make-Up | Kerry Spurrell | On Set Dresser |
| Camera | Robert Cochrane | Dolly Grip |
| Costume & Make-Up | Diana Ladyshewsky | Hairstylist |
| Sound | Robert Ulrich | Supervising ADR Editor |
| Camera | Michael Carella | "B" Camera Operator |
| Lighting | Michael Galbraith | Chief Lighting Technician |
| Camera | Samuel Turturici | Grip |
| Production | Annette Brooker | Production Assistant |
| Production | Adam Bocknek | Production Assistant |
| Editing | Robert Doyle | Assistant Editor |
| Production | Ruthie Brownfield | Casting Assistant |
| Art | Jonathan Kovacs | Assistant Property Master |
| Art | Colin Woods | Assistant Art Director |
| Sound | Anne Couk | Assistant Sound Editor |
| Production | Britt Doughty | Production Assistant |
| Crew | Christine Thomas | Stunts |
| Camera | Richard Emerson | First Company Grip |
| Art | Carlos Caneca | Set Dresser |
| Costume & Make-Up | Beatrice Salazar | Assistant Hairstylist |
| Production | Dane Clark | Casting Assistant |
| Art | Henry Piersig | Leadman |
| Production | Patrick Davis | Production Assistant |
| Production | Trevor A. Weber | Assistant Location Manager |
| Costume & Make-Up | Linda Steeves | Assistant Makeup Artist |
| Editing | Gena Bleier | Assistant Editor |
| Costume & Make-Up | Carol Hartwick | Hairstylist |
| Editing | David Tarnawsky | Assistant Editor |
| Production | Robin D. Cook | Casting |
| Production | Donna Dupere | Extras Casting |
| Sound | Willard Overstreet | Foley Editor |
| Editing | Doug Caron | Assistant Editor |
| Sound | Robin Harlan | Foley Artist |
| Crew | Dave Staples | Transportation Coordinator |
| Crew | Janet Cormack | Scenic Artist |
| Editing | Mary Nelson-Duerrstein | Negative Cutter |
| Editing | Mike Stanwick | Color Timer |
| Art | Marc Kuitenbrouwer | Construction Coordinator |
| Art | Eric Taylor | Construction Foreman |
| Crew | Stuart Mitchell | Transportation Captain |
| Sound | Randy Singer | Foley Mixer |
| Sound | Bob Baron | ADR Mixer |
| Directing | Andrew Shea | First Assistant Director |
| Crew | Donna Feore | Choreographer |
| Crew | Sandra Feldman | Stunts |
| Crew | Vlasta Racki | Stunts |
| Crew | Andrea Eisen | Studio Teacher |
| Crew | Erin Carter | Stunts |
| Crew | Rebecca Stoneham | Stunts |
| Crew | Billy Oliver | Stunts |
| Crew | Taryn Ash | Stunts |
| Crew | Colleen Park | Stunts |
| Crew | Laurene Boutet | Stunts |
| Crew | Natalie Cultraro | Stunts |
| Crew | Kym Kristalie | Stunts |
| Crew | Chauntelle Page | Stunts |
| Crew | Alison Reid | Stunts |
| Crew | Danny Lima | Stunts |
