The phrase "about which customer" is correct and usable in written English.
It can be used when referring to a specific customer in a discussion or inquiry, often in a formal context.
Example: "I need clarification about which customer we are discussing in the meeting."
Alternatives: "regarding which customer" or "concerning which customer".
During the fallow period after the boom, online brokerages have grown smarter about which customers are the most profitable, and are offering different levels of service and price.
In recent years, investigators said, the distributors received telephone instructions from Colombia about which customers to meet at what street corners.
The exhibit "A Scorecard for Selecting Global Accounts" can help suppliers think about which customers might be serious candidates for global account management.
He has one staff member to fill out employee forms, handle his payroll, manage his e-mail list and make all-important choices about which customers will get holiday gifts.
In others, it means actually using the mountains of data that e-tailers have said all along would help speed their earnings growth -- by allowing them to make better decisions about which customers are the most profitable, for instance.
Companies in similar positions should avoid acquiring businesses whose target customer is too different from its own, or have a clear plan for making careful choices about which customers to prioritize.
While Dell's direct business model laid out which value chain activities Dell would do (and which it wouldn't do), the company still had crucial strategic choices to make about which customers to serve and what kinds of products and services to offer.
At the heart of our approach is the recognition that a go-to-market strategy for any innovation involves making choices about which customers to target, what technologies to apply, what organizational identity to assume, and how to position the company against which competitors.
Another frustration: China has little information about which customers are mostly likely to pay their bills.
