Proceedings of the international conference on hydrogen effects in materials, which was held September 9-12, 2012 at Grand Teton National Park, Jackson Lake Lodge, Moran, Wyoming, USA. Previous conferences in this series were held in 1973, 1975, 1980, 1989, 1994, 2002, and 2008, where the venue for the last six conferences has been Jackson Lake Lodge. These conferences have been the premier topical meetings on hydrogen effects in materials, as demonstrated by past attendance, and extensive citations of the conference proceedings in technical literature. The continuation of this conference series is proving to be quite timely, since interest in developing hydrogen as a fuel is casting more attention on hydrogen-materials interactions. The 2012 International Hydrogen Conference will continue the trend of past meetings, where hydrogen effects on mechanical properties of materials is a primary topic.