The last principle on which a decision has to be taken before the ex ante evaluation of an ERP system starts is the go live strategy. One of the critical phases in an ERP implementation is the go live or shakedown.
In this phase, the new ERP system becomes operational, as well as the related new business processes.
Old computer systems are shut down and old ways of working become obsolete.
The organization of the go live is determined by the so-called go live strategy. This strategy determines in which sequence the new users start using the ERP system for their daily work. A go live strategy has to be selected for every unit of the organization that starts to use ERP operationally.
A well-known go live strategy is the big bang: all users start using the new ERP system for their daily work at the same moment. It is obvious that this is a risky strategy, especially when users are spread over geographical locations and the ERP system covers a large part of the operational processes of the organization.
The risk of a big bang can be limited to a certain extent by a good fall back scenario. When such a scenario is used, the old applications as well as the new ERP system are used in parallel during the beginning of the go live. Daily, the new ERP system is being evaluated. When the new system does not work sufficiently well the use of the new system is temporarily suspended, and the organization falls back on the old applications. After the new system has been repaired, a new go live is attempted. As soon as the ERP system has proven to offer sufficient support for the business processes, the old applications and processes are abandoned.
The most popular go live strategy is the go live per function. As a first step in the go live the users in a certain function, often the financial department, apply the new ERP system. All other users continue to use their original applications. As soon as the new system’s operation is considered stable and reliable for this one function, the other functions in the organization, such as manufacturing and sales & marketing also start using it. With this strategy, the risk of the go live is mitigated. For this strategy it is however required to feed the financial modules of the ERP system with manufacturing or other data from the existing applications. This could be done manually, but only for a limited time. In a go live per function, the time between the go live of the first function and the subsequent go lives of other functions can span months; in this case it is recommended to build electronic interfaces between the ERP system and the old applications.
In addition to the big bang and the go live per function, many others go live strategies can be designed. Examples are a location-by-location small bang, a go live per process or per market. In each go live strategy, it is important to determine which data and processes are supported by which system or application at any time during the go live, and which temporary interfaces are required to make sure all applications are fed with the required data.