We are planning to implement Employee Interaction Centre (EIC). We can do it either in CRM or ERP. What is your advice?

If the focus is on native HR functionality requiring process depth within your EIC service offering, then the ERP option is recommended.
Relevant functionalities not yet available with the SAP CRM EIC deployment option include the handling of concurrent employment scenarios employee authentication integration to HR processes and forms.
The SAP CRM solution provides greater depth of Interaction Center related functionality that is not available within the ERP solution.
These functionalities include:
•        Campaign management
•        Case management
•        Multi-tenancy capabilities enabling client switch & BPO environments
•        Standard help desk processing methodology including service request handling  & problem management
•        Intent driven interaction
•        Billing and charging for delivered services
•        User interface flexibility and personalization