Caillat worked with various producers, songwriters, and artists including Greg Wells, Rick Nowels, John Shanks, and Kara DioGuardi. Caillat set up a hi-octane 'writing camp' in Hawaii, inviting familiar collaborators Jason Reeves and Mikal Blue (who co-produced/co-wrote her debut album) and Kara DioGuardi to help with the album. Guitarist David Becker also appears on the album. The deluxe version of Breakthrough was released on August 25, 2009, and includes five bonus tracks.
The album has been met with fair to positive reviews.Michael Lello from Pop Matters gave to the album 7 stars (out of 10) and says that: "On Breakthrough, Caillat wisely builds upon her strengths—the aforementioned disciplined singing approach and girly topics—rather than enter drastic new territory. There’s a consistency throughout the 12 tracks, which is remarkable considering she enlisted some proven hit-makers—co-writer John Shanks (Kelly Clarkson, Alanis Morissette, Sheryl Crow), her producer dad Ken Caillat (who co-produced and co-engineered Fleetwood Mac’s Rumours), and writing partner Kara DioGuardi of American Idol. The industry pros serve to sweeten, not change, Caillat’s sound, which results in a richly textured album, not just a collection of radio-baiting singles, that retains the performer’s personality." The Allmusic review gave to the album 3 stars (out of 5) and says that: "'Breakthrough' it's a creation that's slicker and sleeker than the debut, but fortunately, it's not quite at the expense of Caillat's simple charms". Billboard gave an average review saying: "Breakthrough never quite lives up to its title. But the songs that do diverge from the formula even slightly-like the Greg Wells-produced "Fearless"-offer delightful relief, and perhaps a taste of what could be if the singer were to dig deeper". The Sputnikmusic review was more favorable saying that: "Colbie’s soothing vocals, the warm sound of the music, and the memorable choruses are all well worth listening to this for when the mood for something easy hits you". Jim Farber from Daily News has said that "the inconsequence of Caillat’s sound provides a balm for the near nonstop rejection she suffers in her lyrics and even in those rare tracks where Caillat wins the guy, it doesn’t sound like she’s doing much with him beyond holding hands. Adults may giggle over that. But with songs this catchy, they’re also likely to find themselves singing along".
"Fallin' for You" was released as the album's lead single on June 30, 2009. The single debuted at #12 on the Billboard Hot 100 becoming Caillat's highest chart debut selling over 118,000 digital downloads. The music video was released in July, 2009.
"I Never Told You" is the second single from the album. It was officially released on February 16, 2010. It has peaked at #48 on the Billboard Hot 100.