A method of inhibiting angiogenesis in an individual in need thereof comprising administering an antibody that selectively binds to the extracellular region of human magic roundabout (MR) to the individual. An antibody that has the amino acid sequences i) to iii), the amino acid sequences iv) to vi), or the amino acid sequences i) to vi). i) S A S S S V S Y M Y ii) L T S N L A S iii) Q Q W S S N P L T iv) D Y N L N v) V I N P N Y G T T S Y N Q K F K G vi) G R D Y F G Y. A method of inhibiting angiogenesis in an individual in need thereof comprising administering the extracellular domain (residues 1-467) of MR, or a fragment thereof that inhibits angiogenesis, to the individual. A method of inhibiting endothelial cell migration and/or proliferation comprising administering the extracellular domain of MR, or a fragment thereof that inhibits endothelial cell migration and/or proliferation.