The first season of any reality show is all about getting to know the main cast. Since KUWTK centers around the Kardashian-Jenner household, its original ensemble focused on its eight core family members: Rob Kardashian, Kendall Jenner, Kim Kardashian, Kris Jenner, Caitlyn Jenner, Kylie Jenner, Kourtney Kardashian, and Khloé Kardashian. This was when Kendall and Kylie were considered the only kids in the home, so seeing how everyone moved out to start their own families really makes you think about how much time has passed.

As an executive producer of the show, Kris is just as involved in KUWTK as she was when it launched, and it seems like she'll continue her role until the show's end. While appearing on The Late Late Show with James Corden in September 2019, Kris said she is so proud of the show's success.

"Sometimes it can get a little cringe-worthy, but I think that everything we look back on is such a great lesson and taught us so much. We're here because of the journey we've been on, so I'm just grateful," Kris said.

Despite diving into the beauty world, launching a shapewear line, and studying law, Kim somehow still finds time to film episodes of KUWTK. Her dedication to the show was on full display in a December 2019 episode when Kim got frustrated at Kourtney for supposedly not wanting to film as much as her or Khloé.

"Our job is being open and honest and sharing a lot of ourselves... because if we’re not sharing our lives, then what is the show?" Kim said during a confessional at the time. Kim's drive shows why she's still so invested in KUWTK after all this time.

In a July 15 interview with The View, Khloé said there are times when she feels like quitting, but those thoughts go away as soon as they come. For example, when she remembers KUWTK offers her the opportunity to spend more time with family, she forgets about everything else.

"There’s some seasons that you’re experiencing life at its heaviest and you obviously would want to do anything besides be on camera but when you sign up for the show, you sign up to show the good and the bad," Khloé explained, showing how she's committed to everything her job entails.

In November 2019, Kourtney announced she wouldn't be on KUWTK as much as before. Due to wanting to maintain some privacy, she felt it was best to take a break from the cameras for a little while. "I have been filming the show non-stop for 14 years," Kourtney explained in a July 7 interview with Vogue Arabia. "I was feeling unfulfilled and it became a toxic environment for me to continue to have it occupy as much of my life as it was."

However, just because she won't be on screen as frequently as her sisters anymore, that doesn't mean Kourtney is done with KUWTK. She made it clear her role will just be smaller and she'll have more control of when cameras can follow her around moving forward.

Kendall and Kylie are technically still part of the show's main cast, but they're not as involved as they were when they were kids. That's because Kendall's priority is now in the modeling world, while Kylie is busy running Kylie Cosmetics and taking care of baby Stormi. Due to their solo endeavors, Kendall and Kylie have different contracts that don't require them to be on the show as much as their sisters.

While appearing on Watch What Happens Live in January 2019, Kim explained Rob left the show after Season 7 because he didn't feel like filming all the time. Now, after years of making appearances on the show here and there, Rob may be rejoining the main cast soon.

In July, People reported Rob has been feeling inspired to return thanks to Khloé. "He's ready to be back in the spotlight and he actually seems to look forward to being on the show again," a source reportedly told the publication in July.

Watch Rob make a small appearance in a KUWTK teaser from Aug. 17 below.

Disick wasn't in the opening credits for Season 1, but he was part of the show since the beginning as Kourtney's boyfriend. Over the past decade, fans saw the pair go through many ups and downs in their relationship, like dealing with cheating speculation, experiencing the births of their three children Mason, Penelope, and Reign, breaking up, and learning to co-parent as friends. Even though he's no longer with Kourtney, he still appears on the show frequently.

Caitlyn was a regular cast member for much of the show's duration, but after she released her memoir The Secrets of My Life, which included private details about her relationship with Kris, in April 2017, things changed.

The Kardashians called Caitlyn out for publicizing such personal information. The family not seeing eye to eye likely led to Caitlyn distancing herself from KUWTK. After Season 13, Caitlyn went from being part of the main cast to an occasional guest. Her last appearance was on episode 255 in Season 18, which aired in March 2020.

West became a reoccurring cast member on KUWTK after he and Kim started dating in April 2012. His time on the show only got more significant following the couple's wedding in 2014. Now, fans see West on the show every few episodes.

Through the years, fans have seen Khloé and Thompson go from lovers to exes, to co-parents on KUWTK (and possible lovers again based on the Season 18 trailers). Fans have seen all their dirty laundry — like Thompson's pension for infidelity — aired on TV, but they've also seen their happier moments together, like celebrating their daughter's milestones. Since Thompson is so involved with True's life, it seems he won't stop appearing on the show any time soon.

KUWTK fans saw Odom on screen for the first time during the show's Season 4 premiere, which focused on his and Khloé's wedding.

Unfortunately, the pair split in 2013, but when Odom overdosed in 2015, Khloé was by his side. Odom stopped being a regular cast member in 2016, around the same time he and Khloé's divorce was finalized.

Kylie's ex Tyga's time on KUWTK was short-lived because fans only saw him in a few episodes throughout Season 11. His brief appearances were understandable since he was mainly focusing on his music career when not together with Kylie.

Bailon made her KUWTK debut in a 2008 episode of KUWTK called "Rob's New Girlfriend." After Rob fell head over heels for the actress, she began appearing on the show more.

Fans saw so many milestones in the couple's relationship, like them moving in together and introducing their families to each other for the first time. After their split in 2009, fans caught Bailon on the show when Rob tried to rekindle their romance, but when that didn't work out, fans didn't see her anymore.

While Richie has been a family friend since 2014, her KUWTK debut came in October 2019. Sadly, due to her and Disick breaking up in May, she hasn't appeared on the show ever since. Even if Richie ever got back together with Disick, it seems the star doesn't plan to make another cameo because she wants to break into acting instead.

Humphries' time on KUWTK lasted about as long as his whirlwind romance with Kim. Their wedding was a huge part of Season 6 and a highlight of the series overall. Although the family's referenced him from time to time on the show, he hasn't made an on-screen appearance since he and Kim divorced in October 2011.

Malika has always been so loyal to the Kardashians. Whenever Khloé needed a shoulder to cry on, she was right there as her closest confidant. Malika gave birth to a baby boy in March, which might explain her recent absence from the show.

Just like her sister, Khadijah has been a reoccurring guest on KUWTK for a long time. According to IMDB, her last significant appearance was in episode 146 during Season 10. Just because fans don't see her face on the show as much doesn't mean she isn't tight with the family because Khloé often references hanging out with Khadijah and Malika when talking to her sisters.

Woods occasionally appeared on KUWTK as Kylie's best friend, but she got more attention over on Life of Kylie, the KUWTK spinoff in which her friendship with the youngest Jenner was a focal point. However, after news broke in February 2019 that Woods and Tristan Thompson had kissed at a party while he was still dating Khloé, the family cut ties with her. She stopped appearing on KUWTK after Season 16, but the family referenced their fallout with her throughout Season 17.

Cheban, who legally changed his name to "Foodgod" in 2019, is one of the Kardashian family's oldest friends, and he's especially close with Kim. He's been in so many episodes, but since 2018, fans haven't seen him much, likely due to Cheban pursuing personal projects.

Pippen is another one of the family's OG friends, so much so, she was even there to see Kim's iconic "Fairytale Wedding" to Kris Humphries in Season 6. Every time the sisters needed someone to confide in, The Real Housewives of Miami star was there. As of summer 2020, Pippen hasn't hung out publicly with the Kardashians or appeared on the show for a while, so fans speculate there may have been beef between her and the family behind the scenes.

The new generation of the KUWTK cast involves the family's children. Fans saw Mason, Reign, and Penelope on the show when they were toddlers, but as they've grown older, it seems their parents decided to keep their lives private instead. North has also made a few appearances, but other than these kids, fans have yet to see the other KarJenner children on the show.

As some of the biggest celebrities in the world, the Kardashians are continuously meeting new people, and some become such a big part of the family's lives that they end up guest-starring on the show. Fans appreciate whenever they see a new face on screen because it keeps things fresh. Based on how many different cast members there have been so far, fans can expect to see plenty more in the show's final season and a half.