In the early 2000s, Aukerman took a break from biochemistry and reunited with the Descendents to record a new album.
The recording sessions for Cool to Be You took place with Aukerman in February 2002 at The Blasting Room in Fort Collins, Colorado, with additional recording done in April at Planet of Sound in Wilmington, Delaware, and were produced by Stevenson.
The band recorded the music for the songs live in the studio with minimal overdubbing, and Aukerman's vocals were recorded over the instrumental tracks.
However, these recordings were not released for another two years.
Stevenson explained that the gap of eight years between Descendents albums was due to the band members having children and to his father's death.

For the release of Cool to Be You the Descendents signed to Fat Wreck Chords.
Label head and musician Fat Mike was a longtime fan of the band, and his enthusiasm for working with them was a major factor in their decision to sign to the label.
Stevenson commented that "If you've got the owner of the label saying he wants to put out a record by what is probably his favorite band of all time, that's rad.
That's the best possible position for a band to be in."
The album was preceded by the 'Merican EP in February 2004, followed by the full-length album in March.
Cool to Be You was released in both CD and LP formats, with a cover illustration drawn by Chris Shary depicting the band's Milo caricature drawn on graph paper.

In October 2008, founding member Frank Navetta died after "becoming ill over the course of a few days".
The official website of the Descendents gave its grief to Frank, "We're very sorry to announce that founding member of The DESCENDENTS, and close friend Frank Navetta died on October 31, 2008 after becoming ill over the course of a few days.
This is obviously a huge loss for the DESCENDENTS family.
His contribution to the band, and to music in general can not be overstated.
Frank will be truly missed."

In 2010 the Descendents reunited again for a series of gigs.
According to Milo, the reunion is not an official reformation.
He classified these as "one-off shows", usually occurring when he is able to take advantage of vacation breaks as working as a biologist to perform with the Descendents.

A documentary called Filmage documenting the story behind the Descendents and All premiered at Bloor Hot Docs cinema in Toronto on 15 June 2013.

In May 2015 it was announced by Stevenson that the band had been working on some demo songs for a new album, which could possibly be released mid-2016.
On April 22, 2016, it was announced that the band's next album, Hypercaffium Spazzinate, along with an accompanying EP with 5 bonus tracks from the recording sessions entitled Spazzhazard would be released through Epitaph in July.

On June 7, the debut single from Hypercaffium Spazzinate "Victim of Me" was released on all streaming services.
In July 2016, Milo announced he would be leaving his scientific career to pursue the Descendents full-time, citing burnout with biochemistry and getting laid off from DuPont.
In April 2017, the band released a standalone single titled "Who We Are", a highly political song that laments the Presidency of Donald Trump and repudiates the bigotry, violence and divisiveness that the band feels he has caused.

In a March 2019 interview with OC Register, Aukerman revealed that Descendents were working on a new album: "When we put out the last record we thought, 'OK, I bet we could put out another record after this one and not wait a decade to do it.'
It was such a rewarding experience and you know what?
Our fans deserve better.
They deserve more than a record every decade or so.
We started writing almost immediately after that record was done.
I have been writing and Stephen (Egerton) has really picked up the mantle, too.
Between us I think we have like 20 songs written and Bill (Stevenson) and Karl (Alvarez) have been writing songs as well.
We've done some basic tracking, but it's still a work in progress but I hope we'll have something out by the end of the year."
In the early 2000s, Aukerman took a break from biochemistry and reunited with the Descendents to record a new album. The recording sessions for Cool to Be You took place with Aukerman in February 2002 at The Blasting Room in Fort Collins, Colorado, with additional recording done in April at Planet of Sound in Wilmington, Delaware, and were produced by Stevenson. The band recorded the music for the songs live in the studio with minimal overdubbing, and Aukerman's vocals were recorded over the instrumental tracks. However, these recordings were not released for another two years. Stevenson explained that the gap of eight years between Descendents albums was due to the band members having children and to his father's death.
For the release of Cool to Be You the Descendents signed to Fat Wreck Chords. Label head and musician Fat Mike was a longtime fan of the band, and his enthusiasm for working with them was a major factor in their decision to sign to the label. Stevenson commented that "If you've got the owner of the label saying he wants to put out a record by what is probably his favorite band of all time, that's rad. That's the best possible position for a band to be in." The album was preceded by the 'Merican EP in February 2004, followed by the full-length album in March. Cool to Be You was released in both CD and LP formats, with a cover illustration drawn by Chris Shary depicting the band's Milo caricature drawn on graph paper.
In October 2008, founding member Frank Navetta died after "becoming ill over the course of a few days". The official website of the Descendents gave its grief to Frank, "We're very sorry to announce that founding member of The DESCENDENTS, and close friend Frank Navetta died on October 31, 2008 after becoming ill over the course of a few days. This is obviously a huge loss for the DESCENDENTS family. His contribution to the band, and to music in general can not be overstated. Frank will be truly missed."
In 2010 the Descendents reunited again for a series of gigs. According to Milo, the reunion is not an official reformation. He classified these as "one-off shows", usually occurring when he is able to take advantage of vacation breaks as working as a biologist to perform with the Descendents.
A documentary called Filmage documenting the story behind the Descendents and All premiered at Bloor Hot Docs cinema in Toronto on 15 June 2013.
In May 2015 it was announced by Stevenson that the band had been working on some demo songs for a new album, which could possibly be released mid-2016. On April 22, 2016, it was announced that the band's next album, Hypercaffium Spazzinate, along with an accompanying EP with 5 bonus tracks from the recording sessions entitled Spazzhazard would be released through Epitaph in July.
On June 7, the debut single from Hypercaffium Spazzinate "Victim of Me" was released on all streaming services. In July 2016, Milo announced he would be leaving his scientific career to pursue the Descendents full-time, citing burnout with biochemistry and getting laid off from DuPont. In April 2017, the band released a standalone single titled "Who We Are", a highly political song that laments the Presidency of Donald Trump and repudiates the bigotry, violence and divisiveness that the band feels he has caused.
In a March 2019 interview with OC Register, Aukerman revealed that Descendents were working on a new album: "When we put out the last record we thought, 'OK, I bet we could put out another record after this one and not wait a decade to do it.' It was such a rewarding experience and you know what? Our fans deserve better. They deserve more than a record every decade or so. We started writing almost immediately after that record was done. I have been writing and Stephen (Egerton) has really picked up the mantle, too. Between us I think we have like 20 songs written and Bill (Stevenson) and Karl (Alvarez) have been writing songs as well. We've done some basic tracking, but it's still a work in progress but I hope we'll have something out by the end of the year."
Descendents