Although largely conforming to the formula established by Clark's previous work with Hatch, "Who Am I?" is distinct in its referencing concerns of the 1960s social consciousness, specifically the search for the meaning of life. The November 1967 issue of High Fidelity magazine featured an essay by Glenn Gould: The Search for Petula Clark, which Gould was moved to write after hearing "Who Am I?" on his car radio, the song striking him as a "document of despair [which] catalogues [the] symptoms of disenchantment and ennui" in contrast to the buoyancy expressed in Clark's earlier hits "Downtown", "My Love" and "A Sign of the Times". Gould later observed his essay used Petula Clark "as a jumping off point to examine the whole so-called flower-child generation of the mid-60s."

"Who Am I?" acknowledges the mid-1960s baroque vogue in its incorporation of a harpsichord in its instrumentation.

Despite reaching #21 in the US in late 1966 and being the follow-up to one of Clark's most popular UK hits: "I Couldn't Live Without Your Love", "Who Am I?" stalled at #52 on the UK charts to become Clark's first single since "Downtown" (1964) to fall short of the UK Top 50. The follow-up to "Who Am I?": "Colour My World", also missed the UK charts leaving Clark in need of a major comeback in her native land - which her next release "This Is My Song" effected. In Australia "Who Am I?" reached #42.

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