During the war period, while working as a camp supervisor in the Central Valley, he made numerous drawings of field workers: "It seems to me that the drawings that I began to make of field workers and so on, are among the first things which I consider to have really quite significant quality".
His paintings of the post-war years (1945–48) continued in representational vein reflecting Bay Area street-life and bar scenes, characterised by flattened space with frequent combination of collage elements taken from advertising and newsprint, and increasingly tough gestural brushwork. Smith's humor and social conscience are evident in the works from this period.Smith's most influential and widely known paintings and drawings developed rapidly from the end of the 40's, lasting into the mid-1960s. The influence of Clyfford Still's torn fields of color was apparent from an early stage, alternatively a strident dispersion of roughly applied post-pointillist strokes. By the mid-1950s Smith achieved an entirely independent stylistic language, integrating raw canvas and broad patches of color with a combination of short curving, also ruled linear markings that dance at speed across the visual plane, tightening pictorial space.
Regrettably few paintings comprise the final group of Smith's works, executed in the three years before a Parkinsonian illness prevented further output. Rarely exhibited and little-known, they are an amassing of gestural marks into solid shapes whose tonal contrasts and soft edges create interlocking dramas of pictorial space. Hassel Smith's last works are consistent with his signature West coast sensibility, yet there is a compelling tenderness and fragility.Wikipedia