The answers to these questions are case specific. It will be difficult for to generalize the theory for it. Mostly decision on this depends on the readiness audit result, available strength of consulting human power – both internal and external – relevance of ERP at various units, timeframe, and the budget.
Therefore it is advisable to go for the key modules such as sales order processing, material planning including purchasing and factory management at the first stage. Modules such as human resources, document management, maintenance and even financials can be implemented later. If there is more than one business unit involved it is best to implement in a relatively easy but not untypical unit first then roll out the implementation to the other units.
