System Changeover definition

System changeover is concerned with the smooth shift from one way of doing things to another and the mitigation of disruption to business activities during the changeover. There are three main methods used: phased implementation, direct changeover and parallel running.

• Phased implementation: a staged method whereby one part of the overall system that need changing is changed. If any problems arise, they are limited in scope and therefore non-critical. Once the system has been successfully changed in one area, the other areas can follow suit, with any lessons learned during the initial changeover used to ensure the success of the changeover as a whole.
• Parallel running: Both the old and the new systems run side-by-side, using live data, so that project managers can compare the efficiency and reliability of the new system. Once they’re satisfied, the old system is taken offline and the new system becomes fully active and utilised across the organisation.
• Direct changeover: there’s a single, fixed point where one system stops being used and the new one becomes live. This is the cheapest, quickest and easiest form of system changeover but is also the riskiest – if the system is broken or inefficient, the whole organisation suffers.