What are the Functions of a venture capital?

Cash needed for expansion - working capital etc? In return you will be given to actions outside of your company and the venture capitalist who want to participate in the management of the company. In order to use if you really need the funds and can be found to join a capitalist enterprise - however, your business is not yours from the point of entering? You will be accountable to them naturally all the time - if your business goes well then it may well leave you alone - but if they fight then his other concern is going to have?