Interfirm external networks often lead to industry clusters. These clusters are an agglomeration of people who embody the necessary skills and know-how to fulfill the demands of a particular sector. These relationships create conditions where transactions are more efficient and resources can be shared. They can arise through happenstance where a successful company or institution attracts other businesses to locate in the region around it.  A growing core anchors spin-offs and inspires new firms that need to tap into the specific talent within the region. This dynamic results in more opportunities within a certain field and attracts more talent to the area. The more opportunities and support, the better an individual's chance to find employment if things go wrong at one company or a new opportunity arises. Clusters can also be the result of historical or geographic competitive advantage. While more difficult, they can also be brought about by intentional strategic planning. However they are formed, the fertility of the innovation ecosystem is incredibly important to cluster’s success.

Clusters are a result of time and the evolution of industry within a region. The knowledge embedded within it is greater than the sum of its parts. They create an efficiency and dynamic that cannot be easily replicated. They are an accumulation of the networks and knowledge. They are not easy to create nor are they easy to move elsewhere.