The Common Application recommended on their Facebook page recently that students never give their username and password to anyone who’s advising them with their Common App, that students should opt for safer ways to share their information.  I think that’s up to the student and you certainly shouldn’t share your information if you don’t want to.  But as a middle-ground alternative, here’s a suggestion:    

If you have a counselor advising you through your college applications who will have access to your usernames and passwords, consider:

1. Using a new password that you don’t use for anything else (like email or your bank account).  And make it the annoyingly complicated kind with a number and a capital letter and a special character.

2. Set up a special email address that you use only for college applications, like kevincollegeapps@email.com.

That keeps your application life separate from your personal life (and you get to decide how much access a counselor should have to either of them).