This chapter discusses the application of membrane reactors for hydrogen production through autothermal reforming (ATR) reactions, with particular attention to the ATR of methane as fossil fuel and methanol and ethanol as biofuels. First the concept of ATR is explained, the catalysts used for such reactions are reported, and the traditional reactors are discussed. Afterwards, the membrane reactor concepts are discussed, and two possible configurations, namely the fluidized bed and the packed bed configuration, are discussed and compared. Modeling aspects of both reactors are introduced. Finally, the recent advances in membrane reactors for these reactions and future trends are discussed in the chapter.