Pochoir is a printmaking technique where color is applied by sponges with use of a stencil allowing for variances to the works within an edition. Of the Four Pochoir suite, Frankenthaler: A Catalogue Raisonné Prints 1961–1994 compiled by Pegram Harrison states:
The open stencil worked as her guide to the forms, but each impression sustains its own unique character; therefore the edition should be considered "variant." Sheila Marbain (of Maurel Studios) explained the procedure:
The three of us were holding down the stencil while Helen worked over, around, and on our finders with the liquid acrylics. The process was revised to accommodate Helen's free and spontaneous approach to printmaking. We feld that the technique was very effective. Despite the fact that the prints were made as an edition, eash print has an original, fresh quality recalling the immediacy of a unique watercolor, yet there is no doubt that the prints are very closely related.