Maintaining Backend roles and frontend roles(synchronising)

hello all,

I have a problem, and thats how will I maintain properly both backend roles in R/3 and frontend roles on the PORTAL? like ESS/MM ROLES for portal?

What I mean I can set them up, but I am worried on that if we setup a role for the backend we may not always remember to set up the backend roles if you know what I mean?

we use a template which has the role mapping i.e backend and frontend but how do we succesfully synchronise these 2 roles for each users, as each user will always have both roles setup, but worry is sometimes they wont be IN SYNC with each other?

this is worrying, any ideas?