What Pricing Authority Should Salespeople Have?

The Situation
Companies have various approaches when it comes to the authority given to salespeople when setting client pricing.
Some offer the salespeople no authority on pricing and the management team sets the price on every deal.
Other companies provide salespeople pricing tiers that salespeople must stay within.
A third way this is handled is that companies offer their salespeople tremendous latitude for client pricing.
Your Challenge
What pricing authority should salespeople have? Are there factors (i.e., industry type, product type, business size, salesperson tenure, etc.) that affect your recommendation?