Members of the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family are known to influence development, angiogenesis, coagulation and progression of arthritis. ADAMTS levels and activities are regulated at multiple levels through the control of gene expression, mRNA splicing, protein processing and inhibition by TIMP (tissue inhibitor of metalloproteinases). A recent screen of human cartilage has shown that multiple members of the ADAMTS family may be important in connective tissue homeostasis and pathology. ADAMTS5 (a disintegrin and metalloproteinase with thrombospondin motifs 5), also known as aggrecanase-2 and ADAMTS11, is a member of the family of secreted zinc proteases with a multi-domain structure.