Accessing records within a "team"

Hello,

the whole security level and setup process seems to be quite ok, but we are hitting a wall here:

There are some contacts like: maintenance man
Everybody should be able to see her/his contact info.

The rest is quite restrictive:
Account manager sees only her/his accounts, marketing person only her/his regions leads/contacts etc.

How would we make the janitor visible to everybody?

Thanks,
Chris