Information about visa requirements for travel to Ireland can be found on the web page of the Irish Naturalisation and Immigration Service
The full list of countries requiring a visa is at this web page.
Citizens of the EU, EEA, Switzerland, most countries in America, Australia, New Zealand, Japan and South Korea do not require a visa to enter Ireland. Citizens of other countries may require a visa; please check the web pages above.
Note that while Ireland is a member of the EU, it is not part of the Schengen area, and hence a Schengen visa will not be valid for travel to Ireland.
Letters of invitation for visa purposes will be available upon request for registered conference participants. Please address requests to email@example.com, and include your work address (or the address to which the invitation letter should be sent).
If you are planning to apply for a visa, please inform us at firstname.lastname@example.org, including your nationality and the country where you are intending to apply from. This will enable us to inform the Irish visa authorities and may expedite your application.
Visa applications should be submitted at the earliest possibility, and a minimum of 8 weeks before the conference.