The performance of microfabricated fuel cells with Nafion-coated glass composite membranes was investigated. The performance and durability of the fuel cells with silica glass membranes were improved by casting a thin film of Nafion on the anode side of the thin, phosphosilicate glass membrane. Nafion increased the strength of the glass membrane and provided a better chemical environment for the air-cathode. The use of a two-layer anode catalyst improved the anode performance by increasing the catalyst loading while maintaining catalyst porosity for proton transport. The performance, durability, and fuel utilization of the fuel cells using hydrogen and methanol as fuel were studied. (c) 2005 The Electrochemical Society. [DOI: 10.1149/1.2149293] All rights reserved.