The procedure for identifying mold fungi is described in detail, making it easier to get started with identification practice. Using simplified identification keys, individual, commonly occurring genera can be identified. The genus list refers to further literature, with comments on selected species and specific characteristics. Numerous drawings and illustrations facilitate identification. An introduction to the kingdom of fungi and summary notes on their ecology, mycotoxin production, and the issues of taxonomy complete the content. The actual taxonomy is limited to the essentials for the sake of applicability. This 4th edition of "Mold Fungi and Their Identification" has been completely revised and expanded, while maintaining its practical focus.