Any non-European Union citizen planning to stay within the Schengen area for more than 90 days will need to apply for a residence permit.
In law 3386 of 23 August 2005, the Greek government clarified the residence situation for members of Foreign Archaeological Schools and Institutes such as CIG. Thus, the application process for Canadian Institute members has now been simplified into a two-step process:
Before leaving Canada, you need to obtain a special visa from a Greek consulate
Requirements for Visa
Upon arrival in Greece, you need to apply for a residence permit
Requirements for Residence Permit