What Should a Business Development Function Do to Day?

The business development function has existed for the past ten years, despite how much has changed inside of how beta b buyers want to buy. If i was going to start from scratch to set up a business development function to day, what would they do? How would they be measured? Who would i be looking to hir? And so some of the things that run through my head like, subject matter expertise required. Like these people should be able to provide value. Have potentially done the job of your buyer before. Could be part of a community,. So if you mixed all those things together and put it into a modern go to market strategy then we're in a position where that's what i