The third annual summit will take place on 19 April at One Wimpole Street in London.
Event planners can enter for the chance to win one of five copies of the new handbook, Sustainable Event Management by Meegan Jones.
The comprehensive guide offers advice on how to make events more sustainable.
To enter, send in the answer to the following question to email@example.com by 17 April: What is the name of the new electric car that Nissan plans to build in Sunderland?
The summit, which will be attended by corporate planners, agency groups, venues and suppliers, will focus on extending knowledge, from the basic - such as switching the lights off - to more in-depth topics.
Speakers and panels will cover a range of issues such as transport, energy, waste, procurement, BS8901 and social responsibility.
The programme's speakers will also include Do the Green Thing chief executive James Alexander and Excel London services and 2012 director James Mark.
Exhibitors at the summit will include Zipcar, Vintage Roots, Earthscan, Green Tomato Cars, LRS Consultancy, MJ Design and the host venue.
Winners will be chosen at random on Friday 18 April.