If you wish to immigrate to the US then be ready to deal with an extremely complex procedure. The US immigration system follows a very complex law that derives its power from the Immigration and Naturalization Act. This is the law that oversees the management of some 7 hundred thousand immigrants in the US. It has provisions for governing every aspect related to immigration. It stands on four basic pillars or kinds of immigrants. The first pillar is the family based immigration. This is one of the most important basic principles of US immigration law and policy. It aims at unifying families which have arisen out of cross national marriages. There are strict rules on who constitutes family and who does not. Further there are eligibility criteria even for those who come under this policy. Only people falling in the net on immediate family can immigrate under this category. The law has very clearly defined who constitutes your immediate family and who does not. Spouses, unmarried children under 18 and father/mother of a US citizen, who is above 21 years of age can be counted as immediate family.
The category is that of employment based immigration. There are multiple sub categories under this category such as temporary work permit, permanent work permit or even the permanent residency. This is one of the most critical immigration category because it supplies the nation with the best available work force but this does not mean that any tom dick or harry can immigrate to the US. The law very clearly states that only those people should be allowed to immigrate who can bring value to the country. There is a policy in place which dictates all corporations to furnish reason for why the position for which an immigrant is required cannot be filled with a US national.
Thirdly we have the refugee protection program. Goodwill and welfare of people in need across the globe is one of the stated policies of our constitution. In order to fulfil our duties under this policy every year we open our borders for people who want to take refuge in the US. This process is usually overseen by the United Nations. Finally there is the diversity program category which aims at building cultural diversity in the US. This is by far the smallest category. You can know more about immigration laws and rules by going to the author website of any leading immigration attorney.