Ideally, a formally approved internship should be arranged through a university, with a student visa. To get a visa you must submit to the Russian Consulate in your home country:
- a visa application form
- your original passport, valid at least 6 months beyond the end of the planned trip
- 1 recent passport photo
- a medical certificate proving you are HIV-negative (less than 30 days old)
- either an original invitation letter issued by an authorized organization, or the telex number for an invitation telexed to the Consulate directly by the authorized organization
- a letter of introduction provided by the institution at which you are studying
The student visa takes 14-21 business days and costs around $80 depending on the country of application. To change this visa, for example if you get a job, you must leave Russia. Note that your entry date can be no earlier than 5 days after the visa issue date. Dependents can be included on the invitation and visa. They do not have permission to work.
If it is not possible to enter on a student visa you may wish to apply for a business visa. See: You have a job and need to relocate.