Labour Party leader Ed Miliband was officially welcomed to ACC Liverpool by Chief Executive Bob Prattey as some 11,000 delegates descended on the city for the party's annual conference - the biggest ever event to take place at the river-side venue.
The five day political conference, which has been in the planning for 20 months, represents the largest ever event to be held at ACC Liverpool, comprising BT Convention Centre and Echo Arena.
Over 1,200 staff will be in place to ensure the smooth running of the event, which will bring an economic benefit to the city of £15m and brings ACC Liverpool's total contribution to the city economy to £500m since it opened in 2008.
Some 2,000 national and international press and media will attend, with broadcasts from the BBC'S The Andrew Marr Show, Daily Politics Show and Breakfast News as well as coverage from ITN and Sky News transmitted live from ACC Liverpool.
The Labour Party Conference represents one of the tightest security operations in the North West and has been rigorously planned between ACC Liverpool and city organisations including Merseyside Police, Liverpool Convention Bureau and Liverpool City Council.
Maximum security procedures are in place throughout the week facilitated by the venue's ease of lockdown, effectively creating a secure campus site.
The venue will be used to its full scope for the conference and its associated activities: keynote speeches by Ed Milliband and Harriet Harman will take place in the Echo Arena while breakouts and exhibitions will be held in the adjoining BT Convention Centre.
Hall 1C will become a showcase for Young British Talent hosted by Eddie Izzard while another 500 fringe events will be hosted throughout the venue, in a marquee village adjacent and at various locations across the city.
ACC Liverpool Chief Executive Prattey said: "Labour Party Annual Conference is widely recognised as being one of the most high profile events in the UK and we are delighted to be host venue and the central focus of the Labour Party's activity.
"This is the largest scale event we have staged and we are very much looking forward to seeing the rigorous planning and logistics bear fruit when Ed Miliband takes centre stage tomorrow (Tuesday) for his keynote address."
ACC Liverpool Chairman David McDonnell also commented: "The decision of Labour Party to bring their annual conference to Liverpool demonstrates that our venue and city can host events of national and international significance on a huge scale. This is down to the fact that organisations in both the private and public sector are able to work together towards a common aim. "Praise must be given also to the people of the city for consistently laying on such a fantastic warm Liverpool welcome to conference-goers year after year after year."