**8. Conclusions**

Proteinases have diverse activities in the pathogenesis of COPD. With over 40 years having elapsed, since the initial breakthroughs showed a role for these enzymes in this disease, much work has elucidated many further elements of the roles they play. It is clear that the proteinase-antiproteinase balance is not the sole cause of all the pathology seen, but it continues to be a major contributor and a potential target for future therapies.
