The critical role of materials science and engineering in the development of fuel cell technology is surveyed. The inability to fabricate reliable triple-phase-boundary (tbp) structures involving electrolytes, electronic conductors, and gaseous reactants, severely restricted the progress of fuel cells until about four decades ago (similar to 1960). However at the start of the new millennium, commercialisation of four fuel cell types: polymeric electrolyte membrane (PEMFC), phosphoric acid (PAFC), molten carbonate (MCFC), and solid oxide (SOFC), is now being very energetically pursued. Materials selection for each type of fuel cell is briefly examined, and the predominant engineering issues related to the development of commercial products are summarised. The fabrication, reliability, and cost of the relevant materials is of paramount importance to ensure rapid market penetration. The choice of fuel and relevant infrastructure is also considered, and the crucial role of materials for energy storage (particularly hydrogen) and fuel processing, is emphasised.