FAQ: Who reads your first drafts?

How do you choose your early readers -- the ones who give you helpful criticism while you're still writing and revising?

This is a really important question and is a process that can take some experimentation. Here's what I've decided I need in an early reader:
A person who reads books often and intelligently.
A person who is willing to tell me the hard truth.A person who, nonetheless, tells the truth with respect, i.e., delivers criticism in a way that fortifies me, NOT in a way that tears me...