SAP HCM stand alone product

Hi....I'm a SAP ABAP developer and new to SAP HCM...I want to know if is possible to implement SAP HCM module as a stand alone product without implement FI-CO modules or without having interfaces to another SAP ERP system, my client only need a HR system, they already have and are comfortable with their current systems.....Where can I found information about SAP HCM stand alone implementation if this case is achievable.

Thanks in advance,

Mirko.