Economy can be broken down into around 24 sectors, each sector is composed of many industries. Take banking industry, for example, we know each country has its central bank, which in nature is equal to state-own corporation  or public corporation.  In every country Central bank leads banking industry. It roles include:

- Control pricing, which for banking is interest rates.
-  Provide financing to those industries to which private banks dely lending, since those industries have less financial returns, but public well-being depends on the production by those industries.

Like banking industry, other industry should have the similar structure,  public corporation should lead each industry, the advantages include: 
1. ensure production capacity  that may be colapsed by financial instability.
2. control inflation
3. protect the techology base that may be killed due to corporation death.
4. Ensure the production of key goods and services are controled by hostral countries.