A foreign person who is in the US on H-1B visa can in fact work along with the employer and can stay in United States until the status of their visa is approved.
H-1B visas are issued to people for the desired period of time so they can stay in the US and work along with their employer for that period of time.
The status of an H-1B is also mentioned on a person's departure records and he shall be provided with this during the time of their entry in the US after undergoing immigration clearance or at the time their temporary visa is converted as H-1B visa permit.
They can in fact change to H-1B visa from F-1 student visa or even when they change employers in US.
When leaving the US for a short period of time, like traveling to Mexico or Canada for few days, it is generally recommended that the person has to leave their H-1B visa status behind in the US.
So the status of the H-1B visa can in fact be regained back only under the circumstance when the traveler is admitted back in US after the end of their short trip.
It is recommended that a foreign person is allowed to enter US after they have presented their H-1B visa status to the immigration authorities.
This status is generally stamped on his US passport, so they are advised to keep his passport safely when traveling to nearby destinations like Mexico or Canada or else they might have to lose their H-1B visa status along with their US passport.
The immigration authorities also provides the foreign national person with the H-1B visa status for the desired period of time when traveling to nearby place outside US.
You have to keep in mind that you may get the H-1B visa status stamped on your US passport only after submitting your passport at an US consulate.
The process generally begins by filing for a petition by the employer on their behalf.
Having H-1B stamped on your passport requires a sponsor.
In order to get it stamped on the passport it is important that you need to show that you already are eligible for getting a valid H-1B visa by your employer.
If you are a foreign national then you can apply for H-1B visa by following two different procedures.
You might have to travel to your native country and apply for a valid H-1B visa in US Consulate over there.
You can also travel to Mexico or Canada and apply for an H-1B visa at a US consulate there.
In order to apply for H-1B visa application you might have to travel to your native country as it certainly isn't possible to get a visa permit by mailing the application from a foreign country.
Keep in mind that every consulate has their own working system and consulates never provide an immediate walk- in at the facility for issuing the visa permit.
There are also a number of US consulates that may ask you to file for your H-1B visa application only through an approved travel agent.
You might have to submit your passport along with the visa application form.
After that an interview date is finalized and this can be done over the telephone.