The E-3 visa is similar in many respects to the H-1B visa. Important differences include the fact that spouses of E-3 visa holders may work in the United States without restrictions (unlike other US non-immigrant visas, even the TN visa issued to Canadian and Mexican citizens), even if they are of a different nationality; that the E-3 visa is renewable indefinitely (in two-year increments); and that the application process is much quicker. Australian citizens applying for an E-3 visa are also no longer subject to the 65,000 annual visa limit for H-1B visas; although there is a separate annual quota of 10,500 E-3 visas, this is believed to be much more generous to Australians than requiring them to compete with all other nations for H-1B visas. (One calculation is that the E-3 guarantees Australians 15% of the combined annual total of US visas for persons in specialty occupations, should they want such visas, even though with a population of approximately 23.4 million Australia accounts for only 0.3% of the world’s non-US population.) Visas issued to spouses and children are not included in the E-3 quota and spouses and children do not need to be Australian citizens.