I am running Exchange 2003 on a 2003 Enterprise Server in a one domain forest. We want to start using distribution groups in Exchange so I started creating Global Distribution Groups. I then realized that I can also mail enable existing Security Groups. My question to you all is, what is the best practice? Is it best to create new groups for mail distribution purposes or is it ok to just mail enable the existing security groups? The later seems to be much less work and it already contains all of the users and has the groups name we want to use for Distribution such as HS TEACHER or HS STAFF. Whats are the pros and cons of each approach?