A fastener cartridge comprising: a cartridge body comprising: a deck having a plurality of parallel surfaces (2018a-c) that are offset from each other to form a multistep profile; a first set of fastener cavities; a second set of fastener cavities; and a longitudinal slot extending through said deck, wherein said longitudinal slot is configured to receive a cutting member, wherein said first set of fastener cavities is positioned on a first side of said longitudinal slot and said second set of fastener cavities is positioned on a second side of said longitudinal slot, and wherein each of the first set of fastener cavities and the second set of fastener cavities comprise an opening and the openings are in the plurality of parallel surfaces; a plurality of fasteners removably stored within said cartridge body; and an implantable layer having a plurality of parallel deck contacting surfaces (2036a-c) that are offset from each other to form a multistep profile and that are positioned against the plurality of parallel surfaces in said deck, said implantable layer comprising: a first portion (2020'a) comprising a first thickness, wherein said first portion is adjacent to said longitudinal slot; and a second portion (2020'c) comprising a second thickness, wherein said second portion is positioned laterally with respect to said first portion, and wherein said first thickness is different than said second thickness, characterized in that the implantable layer has a plurality of parallel tissue contacting surfaces (2034a-c) that are offset from each other to form a multistep profile and said first thickness is thinner than said second thickness. a cartridge body comprising: a deck having a plurality of parallel surfaces (2018a-c) that are offset from each other to form a multistep profile; a first set of fastener cavities; a second set of fastener cavities; and a longitudinal slot extending through said deck, wherein said longitudinal slot is configured to receive a cutting member, wherein said first set of fastener cavities is positioned on a first side of said longitudinal slot and said second set of fastener cavities is positioned on a second side of said longitudinal slot, and wherein each of the first set of fastener cavities and the second set of fastener cavities comprise an opening and the openings are in the plurality of parallel surfaces; a deck having a plurality of parallel surfaces (2018a-c) that are offset from each other to form a multistep profile; a first set of fastener cavities; a second set of fastener cavities; and a longitudinal slot extending through said deck, wherein said longitudinal slot is configured to receive a cutting member, wherein said first set of fastener cavities is positioned on a first side of said longitudinal slot and said second set of fastener cavities is positioned on a second side of said longitudinal slot, and wherein each of the first set of fastener cavities and the second set of fastener cavities comprise an opening and the openings are in the plurality of parallel surfaces; a plurality of fasteners removably stored within said cartridge body; and an implantable layer having a plurality of parallel deck contacting surfaces (2036a-c) that are offset from each other to form a multistep profile and that are positioned against the plurality of parallel surfaces in said deck, said implantable layer comprising: a first portion (2020'a) comprising a first thickness, wherein said first portion is adjacent to said longitudinal slot; and a second portion (2020'c) comprising a second thickness, wherein said second portion is positioned laterally with respect to said first portion, and wherein said first thickness is different than said second thickness, a first portion (2020'a) comprising a first thickness, wherein said first portion is adjacent to said longitudinal slot; and a second portion (2020'c) comprising a second thickness, wherein said second portion is positioned laterally with respect to said first portion, and wherein said first thickness is different than said second thickness, characterized in that the implantable layer has a plurality of parallel tissue contacting surfaces (2034a-c) that are offset from each other to form a multistep profile and said first thickness is thinner than said second thickness.