Provided are B cell-activating factor receptor (BAFF-R)-binding molecules, in particular, to human antibodies specific for BAFF-R, including antibody fragments. The present disclosure further relates to recombinant receptors, including chimeric antigen receptors (CARs) that contain such antibodies or fragments, and polynucleotides that encode the antibodies, antigen-binding fragments or receptors specific for BAFF-R. Also provided are CARs which contain extracellular binding domains that bind to BAFF-R and B-lymphocyte antigen CD19 (CD19), genetically engineered cells expressing such CARs, and uses thereof in adoptive cell therapy.