The roll of HR in processing Visa of an employee?

Can any one tell me the how HR process VISA at their end in office. In short pls tell me the roll of HR in processing Visa of an employee.

HR is the Nodal Agency/Dept of all the visas to be processed by a Company. They would be the contact-point for the individuals/dept-heads/respective Embassy or Consulate. Unless you give more details of the purpose & which country [for which the Visa is needed], it could be off-the-mark to give any inputs--since the process varies from country to country.

Every country has their own norms. So I sugest to get in touch with any good travel agent who is doing visa work. They have contact in consulate so can be processed easily. Then as per the country you can make list of documents require to process that country visa.
In our company we do the same. From company side we pay the Visa cost & agent cost.