There are two categories of "Leader" series games by Dan Verssen.
Version 1 games were published by GMT in the early 1990's. These games were standard format games available at retail locations. Boxed with printed maps, counters and rules. These games are currently Out Of Print.
Version 2 games are published by Dan Verssen Games and are a refinement and streamlined version of the original (Version 1) system.
In 2005, Version 2 games became available for download in two formats: A Virtual Tabletop Game using the Vassal Engine for solitaire play on a computer and as a set of PDF files that can be purchased, downloaded and printed for physical play. Two games and three expansions are currently available.
In 2010, DVG began publication of Version 2 "Leader" series games in a standard boxed format with printed maps, counters and rules. Games are typically published on a pre-order schedule. (DVG (Dan Verssen Games) P500 Subscription List)
Version 1 "Leader" series boxed games published by GMT
Version 2 "Leader" series PDF & Vassal games published by Dan Verssen Games (DVG)
Version 2 "Leader" series boxed games published by Dan Verssen Games (DVG)