Identity appears repeatedly in Trust Exercise. In the first section, the teenage characters are trying to figure out their own identities, a process that Choi highlights by flashing forward and explaining how they will be different as adults. "Karen's" narrative in the second section complicates this as she breaks down the multiplicity of characters for which Sarah used her as inspiration, as well as the numerous characters who may have inspired the character of Manuel. Claire struggles with her identity as an adopted child and has difficulty piecing together the identity of her father, who is likely Lord. Mr. Kingsley's identity is also unstable, as he appears in the third section as Lord. Not only has his name changed, but so too has his sexual identity (he is not gay, as the character of Mr. Kingsley is), and his motivations appear more sinister. Choi does not claim that identities should be stable; instead, she presents them as naturally shifting in different circumstances, according to different storytellers, and over the course of time.