We're researching new phone systems and each vendor asks us about our "CRM" software. Phone systems integrated with systems like SalesForce, can pull up customer's records based on their the caller's phone number. Likewise, if you're in a customer's record, you can dial their number by clicking on it.
Does Tessitura have such an integration?
Not the right person to ask, since we don't do any telephone integration, but I do remember a TLCC session on a fairly extensive system built by Jon Ballinger.