The X, Y, and Z Portfolios (published in 1978, 1978, and 1981, respectively) by American photographer Robert Mapplethorpe (1946 — 1989) summarize Mapplethorpe's ambitions as a fine - art photographer and contemporary artist, reflecting the tripartite division of his mature work: homosexual
sadomasochistic imagery (X); floral still lifes (Y); and nude portraits of African - American men (Z).