I agree with TOM, Business Process Outsourcing is not a joke. Consulting process is a well statergized process requiring experts who have process / product knowledge and who are certified in quality processes related to a call center like COPC / SIX SIGMA. It also depends if you are proving consultation for existing processes within a call center or if you want to consult for winning new processes.
I can hear everyone say how to win new projects or clients, You will fail if you are in this business with your motive to bring in new customers. Identify the strengths in the service that your call center can provide to your customers. Please be clear in what you want to do to your partners before asking for a new business.