Abstract: Provided are novel human-derived antibodies specific for Fibroblast Activation Protein (FAP), preferably capable of selectively inhibiting the enzymatic activity of FAP, and chimeric antigen receptors (CARs) directed against the human FAP antigen as well as methods related thereto. In addition, methods of diagnosing and/or monitoring diseases and treatments thereof which are associated with FAP are provided. Assays and kits related to antibodies specific for FAP are also disclosed. The novel anti-FAP antibodies can be used in pharmaceutical and diagnostic compositions for FAP-targeted immunotherapy and diagnostics.