Fuel processing for fuel cells has received considerable attention in the literature. However, most of the reported work focused on the production of hydrogen. With internal reforming fuel cells, the fuel processor can operate at relatively low temperatures to generate a mixture of gases containing hydrogen, methane, and the carbon oxides. The primary challenge for any fuel cell system is to select the most effective reforming scheme for a particular application considering factors such as electric efficiency, operating parameters, system complexity, and costs. In this paper we briefly review fuel processing technologies for fuel cells with particular emphasis on fuel pretreatment for internal reforming fuel cells, and discuss concepts and investigations we have pursued at Ceramic Fuel Cells, Ltd. (CFCL) on processing of gaseous and liquid hydrocarbons for application in CFCL's solid oxide fuel cells.