Businesses are one of the main ways of producing income within tycoons, this will be the primary income source at least for all new players and those in the early development of their tycoons empires.
Each business in the game belongs to a specific sector, this is important as each player has a specialty in one sector which gives them sector bonuses when they purchase a business within their sector.
Permits are required to buy businesses with cash, you can use government points to buy beyond your permit limit, however, if you do use points to buy a business then increase your permits that government bought business now takes up a permit slot! Do not use government points to buy businesses until you are done buying permits unless you really must have that government business.
The max number of buy-able permits is 20. To do this you must have 20 business partners. From then on out each permit costs 40 government points.