While planning your travel and in early time, please be sure about the visa obligation (depending on the country of your origin) for your entry in Greece.
In some countries there are External Service Providers for the visa issues. You will receive the relevant information from the embassies or consulates of Greece.
If an invitation letter is needed, please send a request with your full data by email to firstname.lastname@example.org, indicating in the subject "INVITATION LETTER REQUEST". Additionally provide the email address of the consulate where a copy of this invitation letter and any other document requested must be sent from our side (according to the consulate requirements).