Relive the history of progressive music as it occurred from the early 1990s-onward ... Progression back issues are highly collectible and in limited supply! All back issue prices are postpaid to addresses in the United States and its territories. Back issues ordered from outside the United States are sent airmail at a rate of $9.25 per issue ordered. (Please keep in mind that individual copies of Progression can weigh over 1 pound -- it has a lot of pages, and in some cases a CD is included.)