Of all the issues facing a manager as he thinks about the form of his organization, one of the thorniest is the question of whether to group activities primarily by product or by function. Should all specialists in a given function be grouped under a common boss, regardless of differences in products they are involved in, or should the various functional specialists working on a single product be grouped together under the same superior?

Read full article at: https://hbr.org/1968/11/organizational-choice-product-vs-function