What are good entry barriers?
Do such entry barriers work effectively in service industries (US is now dependent on service industries more than 70%)?
Typically, entry barriers are bad because they foster monopolies (those who are already in the industry will inevitably because monopolies as new firms cannot enter to compete).
This is however one exception and that is patents.
Patents work as entry barriers because new firms cannot produce the products (or services) that are protected by a patent, ...
This solution discusses good entry barriers.