The season consisted of 21 episodes and stars Teri Polo and Sherri Saum as Stef Foster and Lena Adams, an interracial lesbian couple, who foster a girl (Maia Mitchell) and her younger brother (Hayden Byerly) while also trying to juggle raising twin teenagers (Cierra Ramirez and Jake T. Austin) and Stef's biological son (David Lambert).

The season starts with Lena collecting a young foster girl named Callie fresh out of juvie.

On the first day of school, Callie convinces Brandon, the eldest child, to help her collect her younger brother, Jude, from her previous abusive foster home.

Brandon is a promising pianist, who spends hours refining his craft but he soon get distracted by the new girl in his house.

The twins both get suspended from school because Mariana sold her brothers medication to raise money to give to her drug dependent biological mother, Ana.

The Fosters was originally conceived by openly gay creators Bradley Bredeweg and Peter Paige[22] who wanted to write a drama that reflected the "modern American family".

"[23] On July 6, 2012, The Hollywood Reporter, among other sources, reported that Jennifer Lopez and her production company, Nuyorican Productions, were developing the yet-to-be-titled hour-long drama for ABC Family, with Lopez set to executive produce alongside Simon Fields and Greg Gugliotta, as well as showrunners and head writers Peter Paige and Brad Bredeweg.

[33] On February 6, 2013, it was reported that ABC Family had picked up the show, with production set to begin that spring for a summer 2013 premiere.

When recounting the casting process, Bredeweg explained, "[W]e spent tireless hours trying to find the right person for each role.