Moorer covers songs by Nina Simone, Patti Smith, Cat Power, June Carter Cash, Joni Mitchell, as well as her sister Shelby Lynne.

In his review for AllMusic, Thom Jurek wrote that it "is a natural sounding set of covers that runs the gamut from rock and barrelhouse blues, to jazz, country, and traditional and indie folk."

"[1] Holly Gleason of American Songwriter writes, "Strength has always been Oscar-nominee Allison Moorer’s suit-and at a time when she enlists roots wizard Buddy Miller to ply an even more organic stew of instruments, the Alabama-born singer/songwriter makes herself even more vulnerable by jettisoning what she knows for what she feels, thinks, believes.

"[2] Jonathan Keefe of Slant Magazine says, "Moorer belongs in any serious conversation about the finest vocalists in modern popular music, and Mockingbird gives her ample opportunities to showcase her interpretive skills and to push herself in new directions.

"[3] Jim Caligiuri of the Austin Chronicle concludes his review with, "With only one self-penned song, the title track, Moorer's songwriting career is seemingly on hold.