H-1B visa
The US H1B visa is a non-immigrant visa that allows US companies to employ foreign workers in specialty occupations that require theoretical or technical expertise in specialized fields such as in architecture, engineering, mathematics, science, and medicine. Under the visa a US company can employ a foreign worker for up to six years. 
Applying for a non-immigrant visa is generally quicker than applying for a US Green Card, therefore the H-1B visa is popular for companies wishing to bring in staff for long-term assignment in the US.
Visa cap
Individuals are not able to apply for an H1B visa to allow them to work in the US. The employer must petition for entry of the employee. H1B visas are subject to annual numerical limits. US employers can begin applying for the H-1B visa six months before the actual start date of the visa. Employers can apply as soon as April 2, 2012 for the FY 2013 cap, but the beneficiary cannot start work until October 1, 2012.Current immigration law allows for a total of 85,000 new H-1B visas to be made available each government fiscal year. This number includes 65,000 new H-1B visas issued for overseas workers in professional or specialty occupation positions, and an additional 20,000 visas available for those with an advanced degree from a US academic institution. Once the visa cap has been reached, USCIS will stop accepting H-1B petitions for FY 2013 and will not accept new applications until April 2013.
Eligibility
The US H1-B visa is designed to be used for staff in specialty occupations. The job must meet one of the following criteria to qualify as a specialty occupation: - Have a minimum entry requirement of a Bachelor's or higher degree or its equivalent.
- The degree requirement for the job is common to the industry or the job is so complex or unique that it can be performed only by an individual with a degree.
- The employer normally requires a degree or its equivalent for the position.
- The nature of the specific duties is so specialized and complex that the knowledge required to perform the duties is usually associated with the attainment of a bachelor's or higher degree.
- Have completed a US bachelor's or higher degree required by the specific specialty occupation from an accredited college or university.
- Hold a foreign degree that is the equivalent to a U.S. bachelor's or higher degree in the specialty occupation.
- Hold an unrestricted state license, registration, or certification which authorizes you to fully practice the specialty occupation and be engaged in that specialty in the state of intended employment.
- Have education, training, or experience in the specialty that is equivalent to the completion of such a degree, and have recognition of expertise in the specialty through progressively responsible positions directly related to the specialty.
Visa length
The H-1B visa is initially granted for up to three years, but may then be extended to a maximum of six years.Even though the H-1B visa is a non-immigrant visa, it is one of the few US visa categories recognized as dual intent, meaning the H-1B visa holder can apply for and obtain a US Green Card while in the US on an H-1B visa. If you are still in the US on an H-1B visa and wish to remain in the US for more than six years, you can apply for permanent residency in the US to receive a Green Card. If you do not gain permanent residency prior to the expiration of your H-1B visa, then you must live outside the US for at least one year before reapplying for another H or L visa.


