One of the things I love about helping organizations with their awareness program is I'm constantly learning different approaches to changing culture. One of the key things I'm learning is, regardless of your approach if you do not have buy in and support of your internal communications team, your program is dead in the water. The more closely you are aligned with your internal communications, the greater impact you will have. Oddly enough, the larger the organization, the more common I see this challenge happening.
One of the key ways to avoid this problem is get your communications team involved from the beginning. Invite them on day one to help craft and build your program. Even better, see if your communications team can assign a single person as your point of contact for all communication related issues. For one organization I recently worked with, they had a communications person dedicated full-time to help build and communicate their awareness program. Needless to say, they are blowing me away with their program.
Long story short, the better integrated and the more support you have from communications, ultimately the greater your success. If nothing else, take out your director of communications to lunch at least once a month