Personas represent the key decision-makers, influencers and users within target customers. These are highly detailed profiles of the different buyers, users, and stakeholders who engage with the company’s product or service.  Personas help align marketing, sales, and product development efforts by providing a shared understanding of customer needs, pain points, and decision-making processes. A well-defined set of personas ensures that messaging and product features resonate with the right audience.

I require these to be shared objects across the ENTIRE company.  Some functional areas will argue (vociferously) for their own Personas – like one set for sales and marketing, one for product, one for CS, etc.   In my experience, though, that just creates confusion and misalignment and doesn’t really get much better “fit” in terms of either how you go to market or how people us the product.   I’d much rather have a slightly longer list of well-defined, aligned personas then multiple department specific set.  You will have to include in the persona definition, however: 

• Department specific behaviors and considerations – example how they behave in the sales process and how they behave in using the app
• Keep the various functional groups aligned on the personas
• Hold the line on not breaking them out further.