All foreign visitors to India require a valid visa.
A tourist visa, valid for 90 days from the date of entry, can be obtained from any Indian embassy, high commission or consulate.
If you intend to leave India and return within the 90-day period (such as from a trip to Sri Lanka or Pakistan),
then it is worth applying for a double- or triple-entry visa.
An extension for a further 90 days can be given to a tourist visa by the Foreigners Regional Registration Office in Bombay (Annexe 2, Office of the Commissioner of Police, Dadabhoy Naroji Road, tel. 268 111).
If a visit extends beyond 90 days, an Income Tax Clearance Certificate is required at the time of departure. This is available from the main tax office in Bombay.