Rand indicated that the primary theme of The Fountainhead was "individualism versus collectivism, not in politics but within a man's soul." Apart from scenes such as Roark's courtroom defense of the American concept of individual rights, she avoided direct discussion of political issues. As historian James Baker described it, "The Fountainhead hardly mentions politics or economics, despite the fact that it was born in the 1930s. Nor does it deal with world affairs, although it was written during World War II. It is about one man against the system, and it does not permit other matters to intrude."
Rand dedicated The Fountainhead to her husband, Frank O'Connor, and to architecture. She chose architecture for the analogy it offered to her ideas, especially in the context of the ascent of modern architecture. It provided an appropriate vehicle to concretize her beliefs that the individual is of supreme value, the "fountainhead" of creativity, and that selfishness, properly understood as ethical egoism, is a virtue.
Peter Keating and Howard Roark are character foils. Keating practices in the historical eclectic and neo-classic mold, even when the building's typology is a skyscraper. He follows and pays respect to old traditions. He accommodates the changes suggested by others, mirroring the eclectic directions, and willingness to adapt, current at the turn of the twentieth century. Roark searches for truth and honesty and expresses them in his work. He is uncompromising when changes are suggested, mirroring modern architecture's trajectory from dissatisfaction with earlier design trends to emphasizing individual creativity. Roark's individuality eulogizes modern architects as uncompromising and heroic.
The Fountainhead has been cited by numerous architects as an inspiration for their work. Architect Fred Stitt, founder of the San Francisco Institute of Architecture, dedicated a book to his "first architectural mentor, Howard Roark". Nader Vossoughian has written that "The Fountainhead... has shaped the public's perception of the architectural profession more than perhaps any other text over this last half-century." According to renowned architectural photographer Julius Shulman, it was Rand's work that "brought architecture into the public's focus for the first time," and he believes that The Fountainhead was not only influential among 20th century architects, it "was one, first, front and center in the life of every architect who was a modern architect."