Although mineral hazards are generally not well established in the public consciousness compared to other natural hazards, they can adversely affect public health and safety and the environment. The term “mineral hazards,” as used here, includes certain naturally occurring earth materials and sites of man-made activities related to them, such as mining and oil drilling. Since the 1990s, the California Geological Survey has conducted many studies of mineral hazards in California in response to an increasing number of requests from government agencies, private industry, and the public. These studies have focused mostly on naturally occurring asbestos, radon, and various metals, such as mercury and cadmium. The mineral-hazard maps and companion reports produced from these studies are typically at statewide and regional scales. They are designed for use by nongeoscientists and geoscientists alike in an effort to educate these groups about mineral hazards and to help in mitigation of those hazards. These products indicate the likelihood of the occurrence of a mineral hazard at a given location, but not the associated health risk. Geographic information systems (GIS) are used to manage and analyze data, and to design the maps. The variety of products developed ranges from traditional paper maps to thematic digital layers for use in a GIS. This range of products increases the likelihood that a greater number of people will use the information. The maps and reports have been used in many applications, and additional applications await development as awareness of mineral hazards and the need for mitigation of them increase.