Is Intention Enough?

I wonder whether intention is all that really matters. Don't you think non-energy therapists seriously INTEND that a screaming baby quiet down? And, don't healers INTEND that their clients/patients get the benefits they are coming for? And I am sure the client/patient INTENDS that they get well - otherwise why would they be sitting in your office? There's your extra "power" on the issue - (where two or more are gathered...). But... (and I'm really just playing Devil's advocate, here)... there's another piece to the puzzle besides intention. So I'm wondering what people think it is.