Such authorisation must be in place before the Directorate of Immigration (UDI) can process a residence permit application for skilled workers for occupations such as doctors and nurses. You can be granted a residence permit as a skilled worker or a specialist even if your offer of employment is not for a continuous period, and you can change employers without having to submit a new application.
 
Contact information for the Norwegian Registration Authority for Health Personnel (SAFH):
P.O. Box 8053 Dep, NO-0031 Oslo
Tel. (+47) 21 52 97 00
Fax (+47) 21 52 97 03
Email: postmottak@safh.stat.no
Visiting address: Calmeyersgate 1, NO-0183 Oslo 
 
You can also read more about how to proceed to obtain an authorisation or a licence on SAFH’s website.