The organizing team has negotiated special rates for attendees with the Holiday Inn Lisbon-Continental within a 15 min walk from the Holiday Inn Lisbon where the conference is taking place.
Just download the booking form, fill up with your details, and send the filled form before the 26th June directly to the hotel.
You can also stay in a number of other hotels nearby. Please start here http://www.booking.com/hotel/pt/holiday-inn-lisboa.pt-pt.html and then look for alternatives using the map feature.