Lomborg arranged the first "Copenhagen Consensus" conference in 2004 and has planned to arrange a similar conference every fourth year. The second was held in 2008 and the third in 2012. In addition, some other local conferences have been held along the same lines.

Comments to the conferences are given here:

Text on Copenhagen Consensus 2004
Text on Copenhagen Consensus 2008
Text on Copenhagen Consensus 2012 .

The conferences are set up in such a way that short-term problems will inevitably get a higher priority than long-term problems. As the climate issue is a long-term problem, it will always get a low rank. And indeed, the 2004 conference resulted in climate problems being given the lowest of all ranks.

How this comes about, is explained in more detail in Lomborg-errrors´ pages on the 2004 conference, and especially in the pages about discounting and discount rates. 
I have also written a page on the concepts "cost-efficiency" and "cost-benefit".

Text on Copenhagen Consensus 2004
Text on discounting
Debate between Fog and Lomborg on cheating with discount rates
Cost-effectiveness versus cost-benefit

Although the basic criticism of the whole set-up of the conferences is found in the text on the 2004 conference, there are some additional critical comments on the 2008 conference and the 2012 conference. For instance, in the 2012 conference, it is obvious that the ranking of the projects is subjective and does not clearly follow the ranking of the benefit-cost-ratios. 

According to Lomborg, Copenhagen Consensus 2004 has stimulated increased funding for the efforts against malaria and HIV/AIDS. Has this funding been worthwhile? Did the effort actually pay off as well as postulated in Copenhagen Consensus 2004? Can the effort stand up to a cost/benefit analysis? This is discussed here:

Analysis of the actual efforts and their outcome