Abstract: A collapsible cylindrical shipping container and joint-forming tape structure therefor is disclosed, wherein the cylindrical side of the container is formed of at least two relatively stiff but flexible sheet wall members having mating edges joined by a tape structure of X-like configuration permitting the wall members to be flexed from a normal collapsed, face-to-face position into an expanded volume-defining position. This latter relationship is maintained by the insertion of end closure means in at least one end of the container thus formed. A joint-forming tape structure used in the container is also disclosed.