Traditionally, the consulting industry charged on a time and materials basis, billing for staff consultants based upon the hours worked plus out-of-pocket expenses such as travel costs. During the late 1990s and early 2000s, there was a shift to more results-based pricing, either with fixed bids for defined deliverables or some form of results-based pricing in which the firm would be paid a fraction of the value delivered. The current trend seems to favor a hybrid with components of fixed pricing and risk-sharing by both the consulting firm and client.