An article of footwear comprising: an upper; a sole assembly ; the sole assembly including a midsole and an outsole ; wherein: the midsole includes a fluid-filled bladder element including a polymeric material that has a surface with an impression (12B; 12C; 12D); the fluid-filled bladder element further including a first polymeric sheet bonded to a second polymeric sheet to form a peripheral seam in the fluid-filled bladder element that at least partially seals an internal cavity that retains fluid; a portion of the bladder element is blocked from view by said one of the midsole , the outsole , or by the article of footwear , wherein the polymeric material comprises the first polymeric sheet that comprises a gas barrier polymer and has a first thickness; wherein the impression (12B; 12C; 12D) has a maximum depth into the first polymeric sheet of not more than about one-half of the first thickness such that the gas barrier polymer is not compromised by the impression (12B; 12C; 12D); wherein at least a portion of the outsole is substantially transparent; wherein the fluid-filled bladder element is secured to the outsole ; and wherein the impression (12B; 12C; 12D) is exposed to view through the portion of the outsole that is substantially transparent. an upper; a sole assembly ; the sole assembly including a midsole and an outsole ; wherein: the midsole includes a fluid-filled bladder element including a polymeric material that has a surface with an impression (12B; 12C; 12D); the fluid-filled bladder element further including a first polymeric sheet bonded to a second polymeric sheet to form a peripheral seam in the fluid-filled bladder element that at least partially seals an internal cavity that retains fluid; a portion of the bladder element is blocked from view by said one of the midsole , the outsole , or by the article of footwear , wherein the polymeric material comprises the first polymeric sheet that comprises a gas barrier polymer and has a first thickness; wherein the impression (12B; 12C; 12D) has a maximum depth into the first polymeric sheet of not more than about one-half of the first thickness such that the gas barrier polymer is not compromised by the impression (12B; 12C; 12D); the midsole includes a fluid-filled bladder element including a polymeric material that has a surface with an impression (12B; 12C; 12D); the fluid-filled bladder element further including a first polymeric sheet bonded to a second polymeric sheet to form a peripheral seam in the fluid-filled bladder element that at least partially seals an internal cavity that retains fluid; a portion of the bladder element is blocked from view by said one of the midsole , the outsole , or by the article of footwear , wherein the polymeric material comprises the first polymeric sheet that comprises a gas barrier polymer and has a first thickness; wherein the impression (12B; 12C; 12D) has a maximum depth into the first polymeric sheet of not more than about one-half of the first thickness such that the gas barrier polymer is not compromised by the impression (12B; 12C; 12D); wherein at least a portion of the outsole is substantially transparent; wherein the fluid-filled bladder element is secured to the outsole ; and wherein the impression (12B; 12C; 12D) is exposed to view through the portion of the outsole that is substantially transparent. <EOS>