System i Leg, which translates to System of Play, was the natural progress of LEGO Mursten and is the foundation of L:EGO sets today. Designed by Godtfred Kirk Christiansen who organized the existing LEGO Mursten sets and modeled new designs around a single, common theme - a townscape or street scene. After nearly a year of development the result was the LEGO Mursten System i Leg (System of Play). The System i Leg was unveiled at the Nürnburg Toy Fair in February 1955. The original Automatic Binding Bricks sets and then LEGO Mursten sets were continued to be manufactured under the System i Leg theme.
1958 LEGO Sets
1958 was yet another historical year for the LEGO Group with its founder, Ole Kirk Christiansen, passing away and his son Godtfred Kirk Christiansen taking full leadership of the LEGO Company. LEGO continued to expand their operations and by 1958 there were 140 employees in Billund. This was also the year that the LEGO brick was completely redesigned into the modern brick we see today. While The System of Play was selling well in several European markets, but it was still limited by the basic design of the original brick.