Mariska Hargitay is a trained rape crisis counselor.

According to an article in TV Guide, cast members are often approached by sexual abuse survivors, who thank them for portraying these types of stories on the air correctly.

Ice-T was originally contracted for only four episodes, but he enjoyed working on the series so much that he asked to join the cast permanently.

Richard Belzer carried his role of Detective John Munch over from Homicide: Life on the Street (1993) and Homicide: The Movie (2000). He also played John Munch in Law & Order (1990), which had several crossover episodes with "Homicide", an episode of The X-Files (1993), an episode of The Beat (2000), an episode of Law & Order: Trial by Jury (2005), the season three finale of Arrested Development (2003), and an episode of The Wire (2002). This is a record for appearances by an actor playing the same character on different programs. Detective John Munch was also played on Sesame Street (1969), voiced by Joey Mazzarino.

For the first twelve seasons of the show, the majority of the episode titles were a single word or initialism (with a handful of exceptions). From seasons thirteen to seventeen, the pattern changed to one in which episodes have a two-word title with the number of letters matching the season number. However, from season eighteen onwards, the episode titles follow no fixed pattern.

Mariska Hargitay keeps a photo of her mother Jayne Mansfield on her desk on the set.

Peter Hermann (Attorney Trevor Langan in thirty-two episodes) is Mariska Hargitay's real-life husband.

After several years of playing Detective Olivia Benson and being exposed weekly to issues of sexual assault, domestic violence, and child abuse, in 2004 actress Mariska Hargitay started a foundation (called Joyful Heart) to help heal survivors' trauma and bring an end to the overwhelming backlog of untested rape kits and un-or under-investigated rape cases. In 2018 Hargitay produced an HBO documentary, "I Am Evidence," about the enormous backlog of untested rape kits in police custody across America.

Richard Belzer originally asked Dick Wolf if Munch could join Law & Order (1990) as Lennie Briscoe's new partner. But Jesse L. Martin had already been cast. Belzer later heard about this new series, and asked to join, on the condition that Dean Winters be cast as his partner. Winters was still under contract with Oz (1997), and had to leave the show after the first thirteen episodes. Winters returned as a recurring cast member in the fourteenth season.

Odafin's (Fin's) last name, Tutuola, means "the gentle one" in Yoruba.

Two years before joining the cast as a series regular, Diane Neal (Casey Novak) appeared in an episode playing a woman accused of raping a male stripper.

Christopher Meloni was starring on Oz (1997) simultaneously with this series. He eventually left "Oz" because he felt that he could no longer do both shows at the same time. But Meloni missed "Oz", and decided to return the next season. He decided that being able to work on two great shows simultaneously was worth the physical and emotional toll.

The series was originally proposed under the title Sex Crimes, and unrelated to the Law & Order (1990) brand. NBC thought the title was too harsh, and after discussions between network executives and Dick Wolf (creator of Law & Order (1990)) it became part of the Law & Order brand, debuting as Law & Order: Special Victims Unit (1999).

Over the course of the series, Mariska Hargitay has been completely absent from only nine episodes.

After the World Trade Center attack on September 11, 2001, NBC ordered the opening credits for the 2001-2002 season re-edited to remove images of the ill-fated buildings.

The second longest-running and most successful spin-off of Law & Order (1990). The franchise includes: Law & Order (1990), Law & Order: Special Victims Unit (1999), Law & Order: Criminal Intent (2001), Law & Order: Trial by Jury (2005), Law & Order: UK (2009), Law & Order: LA (2010), and Law & Order True Crime (2017).

The only prime time drama to be spun off from two separate shows: Law & Order (1990) and, through the character of Detective John Munch, Homicide: Life on the Street (1993)

Rafael Barba (Raúl Esparza) is this show's first regular male Assistant District Attorney.

At the start of season thirteen, episode titles were no longer one word. Season thirteen is also the first season without Detective Elliot Stabler (Christopher Meloni).

Before Kelli Giddish landed her role as Detective Amanda Rollins, she first appeared as a rape victim by the name of Kara Bawson in season eight, episode twelve, "Outsider".

Many of the actors on the show previously starred on the HBO drama Oz (1997) including Dean Winters and BD Wong. Most notable, and ironic, is Christopher Meloni (Detective Elliot Stabler) who played a sadistic rapist and murderer on Oz, and then hunted them on this show. In addition, many guest stars have also appeared in this show and Oz. Reg E. Cathey has the same last name of "Querns" in both shows. Kirk Acevedo, J.K. Simmons (as Emil Skoda), Michael Potts, Lee Tergesen, Kathryn Erbe, Harold Perrineau, Robert John Burke (as Lieutenant Tucker), Scott William Winters (Dean Winters brother who has played a police officer), R.E. Rodgers, as well as many other cast members have appeared on both television programs.

The series has been the longest currently running American live-action primetime television series since the cancellation of Law & Order (1990) in 2010. It is therefore the last remaining such series to have premiered in the 1990s.

Olivia and Elliot were named after producer Dick Wolf's children. The name Olivia shows up in Benjamin Bratt's television family (as one of Rey's daughters), then there's Dr. Olivet.

Season eighteen originally included an episode titled "Unstoppable", loosely based on the allegations of sexual assault made against Donald Trump. It was postponed before the 2016 presidential election, and shelved indefinitely in 2017.

Many members of the main cast in the Law & Order universe usually have a guest spot on one of the shows before they become regular cast members. Peter Scanavino (Sonny Carisi) is the only member of the Law & Order cast to have had a guest starring role on four of the six Law & Order series before landing his role.

Until the fourth episode of season twelve, the precinct scenes were filmed in North Bergen, New Jersey. After this episode, the show moved its studio space to the Chelsea Piers section of Manhattan that was previously occupied by Law & Order (1990).

Jennifer Love Hewitt was considered for the role of Detective Amanda Rollins, after previously guest starring as Vicki Sayers in season twelve, episode three, "Behave".

First season regular guest star Chris Orbach, who played Ken Briscoe, is the son of Jerry Orbach, who played Lennie Briscoe on Law & Order (1990). Ken Briscoe is Lennie's nephew.

According to executive producer Ted Kotcheff, the lead parts of Detective Olivia Benson and Detective Elliot Stabler came down to three actors and three actresses: Mariska Hargitay, Reiko Aylesworth, and Samantha Mathis for the role of Benson, and Christopher Meloni, Nick Chinlund, and John Slattery for the role of Stabler.

Season one is the only season in which Christopher Meloni is credited as "Chris Meloni".

Peter Scanavino made his debut as janitor Johnny Dubcek in season fourteen, episode thirteen, "Monster's Legacy", before he joined the team as Dominick "Sonny" Carisi, Jr., at the start of season sixteen.

Season thirteen marked the first time that this show was broadcast without any other Law & Order branded shows on the air (a position that it had maintained until Law & Order True Crime (2017) aired). Law & Order (1990) ended in 2010, while Law & Order: Criminal Intent (2001) and Law & Order: LA (2010) ended in early 2011, several months before season thirteen premiered.

Season eighteen marks the first time in which Tamara Tunie (Dr. Warner) does not appear.

Season nine has the distinction of having the largest number of main cast members with nine. The season nine cast comprised: Mariska Hargitay, Christopher Meloni, Richard Belzer, Diane Neal, Ice-T, Adam Beach, BD Wong, Dann Florek and Tamara Tunie.

As of the end of season seventeen, Olivia Benson and Dominick Carisi, Jr. are the only detectives to have not been shot in the line of duty. However, Benson was stabbed by Victor Paul Gitano in season seven's "Fault."

Having played Olivia Benson for 20 seasons since 1999, Mariska Hargitay is the longest serving actress in the same role in the history of American live-action prime-time television. At the beginning of Season 20, she surpassed the record held by Amanda Blake, who played Miss Kitty Russell in Gunsmoke (1955) from 1955 to 1974. The only male actors to have played a character for 20 or more seasons in American live-action prime-time television history are James Arness as Marshal Matt Dillon in Gunsmoke (1955) from 1955 to 1975, Kelsey Grammer as Dr. Frasier Crane in Cheers (1982) from 1984 to 1993 and Frasier (1993) from 1993 to 2004 and Richard Belzer as Detective John Munch in Homicide: Life on the Street (1993) from 1993 to 1999 and Law & Order: Special Victims Unit (1999) from 1999 to 2013.

Several of the main characters have served in the United States Military in some capacity. Dr. Warner was in the Air Force, Detective Stabler was in the Marines, Captain Cragen was in the Green Berets (as revealed on the original Law & Order (1990)) and Detective Tutuola was an Army Ranger.

In season fifteen, it appears that Detective Olivia Benson (Mariska Hargitay) now has a larger, fourteen carat, rectangular necklace charm of the same earlier design. She received it from her psychiatrist after her kidnapping and torture, where the original had been held as evidence at the time.

The baby character Noah Porter was played by twin babies, Skyler Dubow and Bradley Dubow (but mostly Bradley). However, in season seventeen and eighteen, the role of Noah was played by Jack Nawada-Braunwart. In season nineteen, the character was once again re-cast, and is currently played by Ryan Buggle.

Although viewers had long wondered if the character George Huang was gay (as is BD Wong), his homosexuality was not verified until season eleven, episode five, "Hardwired". Even for a show and a franchise that is notoriously parsimonious with personal information about its characters, that is an extraordinarily long time for basic personal information to be withheld about a regular character on a television series (by contrast, both Detectives Elliot Stabler and Olivia Benson were established as heterosexual during the show's first season through dialogue and subplots about Stabler's marriage and Benson's dating habits).

This series shared many cast members with ER (1994), including Mariska Hargitay, John Cullum, Kellie Martin, Erik Palladino, Michael Michele, David Krumholtz, Mare Winningham, Leland Orser, Maria Bello, CCH Pounder, Donal Logue, Alex Kingston, Gloria Reuben, and Elizabeth Mitchell.

The photo in the opening credits for Dann Florek (from the beginning of the show) and Ice-T (starting with the second episode of season two) did not change until season nine, when the entire cast received updated photos (coinciding with the debut of Adam Beach). The photo for Mariska Hargitay has changed seven times (season one has one photo, seasons two through four, and the first four episodes of season five have a second, the rest of season five has a third, seasons six through eight have a fourth, seasons nine and ten have a fifth, seasons eleven through fourteen have a sixth, and season fifteen to the present have a seventh). Christopher Meloni, Richard Belzer, and BD Wong got new photos starting with the fifth episode of season five(coinciding with the debut of Diane Neal as Assistant District Attorney Casey Novak) before they all received new photos in season nine. Diane Neal had one photo for season five, a second for seasons six and seven, a third for season eight, and a fourth for season nine. Tamara Tunie, who first appeared in the opening credits in season seven, received a second photo for season eight, and a third photo for seasons nine through twelve, before she was removed from the credits in season thirteen.

The following statement appears at the beginning of every episode: "In the criminal justice system, sexually-based offenses are considered especially heinous. In New York City, the dedicated detectives who investigate these vicious felonies are members of an elite squad known as the Special Victims Unit. These are their stories."

Detective Benson's full name is Olivia Margaret Benson.

Gary Sinise was the first choice to play Elliot Stabler. He would go on to star as head New York Crime Scene Investigator Mac Taylor in CSI: NY (2004) and then as Senior FBI Supervisory Special Agent Jack Garrett in Criminal Minds: Beyond Borders (2016).

Pop star Taylor Swift is such a fan of the show that she named her pet cat "Olivia Benson" in tribute to the lead character.

Uses a re-mixed version of the theme music from Law & Order (1990).

To date, season nine is the shortest season of the series, consisting of only nineteen episodes.

Detective Elliot Stabler's shield number was 6313. Detective (later Lieutenant) Olivia Benson's shield number is 4015 (and then 01139 as a Sergeant). Detective Odafin "Fin" Tutuola's shield number is 3198. Detective Nick Amaro's shield number is 0840. Detective Dominick Carisi, Jr.'s shield number is 0188. Detective Amanda Rollins's badge number is 0458.

Ice-T (Odafin Tutuola) & Peter Hermann (Trevor Langan) also worked together on episode 2.11, Younger: Secrets & Liza (2016), of Younger (2015) as Himself and Charles respectively.

Many cast members from the Netflix series Orange Is the New Black (2013) have made appearances.

This show has frequently used The City University of New York Lehman College campus in Bronx, New York, as a school location.

Prior to season thirteen, season seven was the only one in which Isabel Gillies (Kathy Stabler) did not make an appearance.

Isabel Gillies and Daniel Sunjata, who had recurring roles as Kathy Stabler and a CSU technician, respectively, both played murder suspects on Law & Order (1990); Gillies in season eight, episode twenty-one, "Bad Girl", and Sunjata in season fifteen, episode twelve, "Mammon".

With the commencement of its fifteenth season in September 2013, the series surpassed Knots Landing (1979) as the longest running live-action spin-off series in American prime time television history. Knots Landing (1979), a spin-off of Dallas (1978), ran for fourteen seasons from 1979 to 1993.

ADA Rafael Barba is played by Raúl Esparza, a Broadway star with many award nominations and awards. Coincidentally (or maybe not), in a deleted scene Barba mentions he is going to be seeing Hamilton, one of the most famous Broadway shows to date.

In season eight, episode ten, "Scheherazade", Paget Brewster (Supervisory Special Agent Emily Prentiss on Criminal Minds (2005)) played the daughter of Brian Dennehy, a dying criminal. She returned with a different name as the District Attorney of the Public Integrity Unit.

When the 20th season opener, Law & Order: Special Victims Unit: Man Up (2018), aired on 27 September 2018, SVU tied the record for the most seasons for a scripted prime-time drama series on American television. The record was set by Gunsmoke (1955) and first tied by Law & Order (1990).

Amanda Rollins is originally from Loganville, Georgia. In reality, Kelli Giddish was born in Cumming, Georgia, which is 33 miles northwest of Loganville.

Until season fifteen, Detective Olivia Benson's address was 203 West 89th Street Apartment 4E (or 4D, depending on the episode).

Actor Dylan Walsh guest starred on the show playing 2 different characters. The first time on the season 8 episode "Annihilated" and then again on the season 20 episodes "Man Up" and "Man Down"

Seasons six, seven, thirteen and nineteen mark the only seasons in which Captain Ed Tucker (Robert John Burke) did not appear.

It was announced that the series was renewed for a 21st season, setting a record for the longest prime time live action American TV show. This also set a record for Mariska Hargitay who has played Olivia Benson for 20 consecutive seasons will again play Benson for her 21st consecutive season overtaking James Arness of "Gunsmoke" for most consecutive seasons as one character.

Many cast members from The Wire (2002) appeared on this show.

During season eleven, Stephanie March was added to the opening credits but only for the episodes in which she appeared.

When Law & Order SVU was renewed for its 21st season, it beat the record for longest running live-action prime-time series originally set by Gunsmoke (1955). However, Gunsmoke still holds the record for more episodes (635 vs 458) due to longer production run and in order for SVU to surpass that record it would have to run till season 28.

If it reaches toward the end of its 22nd season, it will become the fourth prime time, scripted TV series (after Lassie (1954), Gunsmoke (1955) and The Simpsons (1989)) to reach its 500th episode.

Munch has several books about the JFK assassination conspiracy on his desk as well as pictures and even a decorative plate with JFK's face on it. Richard Belzer has investigated and written books about the JFK conspiracy and his character Munch is a conspiracy sleuth himself.

Sam Waterston who played district attorney Jack McCoy appears on both Law and Order and Special Victims Unit

The episode where the husband murdered his wife and 2 children is based on the Chris Watt's murder case.