On April 7, 2009, IBM celebrated the mainframe’s 45th year. Drawing on its roots in punch-card tabulators, the machine has come a long way to become many customers’ preferred e-business solution. Throughout its lifetime, IBM’s strategy adapted the machine to the changing market. During the late 1960s, the introduction of the System/360 provided customers with compatibility and scalability across various computer lines. Popularity of the system began to suffer during the client/server era of the 1990s but it quickly recovered as the z Series server line was developed to support e-business solutions. IBM’s strategy made the mainframe successful but continued improvements are still necessary to ensure its future success. / text