The present invention relates to an antibody or functional fragment thereof which binds to a mammalian (e.g., human) CC-chemokine receptor 1 (CCR1) or a portion of the receptor and blocks binding of a ligand to the receptor. The invention further relates to a method of inhibiting the interaction of a cell bearing mammalian CCR1 with a ligand thereof, and to use of the antibodies and fragments in research, therapeutic, prophylactic and diagnostic methods.