The work of construction companies is divided into two parts The first: - is the operation of others meaning that the construction company to build facilities for others Second: The real estate investment in the sense of the construction companies to build for their own and sell what you are building such as residential buildings tourist villages and other Part I Operating for third parties First: Parties 1- The contracting company: - It is called the general contractor, which is the company assigned to implement the project and is the only party responsible to the client, ie the owner 2. The Subcontractor: - One of the parties to which the general contractor assigns some works to him to implement them and does not have any responsibility to the client as the official is the general contractor 3 - Client: - The owner is any body that was assigned to the general contractor to implement the project 4- Consultant: - He is the observer of the project in terms of implementation and selected by client