Trailer video for the 2016 World Cosplay Summit which will be held on July 30 to August 7 in Japan. The video shows some history of the convention, plus clips from the cosplay competition (presumably from 2015), parade and side events.
The WCS is held over a one week period where representatives from different countries visit various parts of Japan, including Akihabara, Kyoto and Sendai, to promote the Japanese youth culture and its ability to connect internationally. The finale is usually held in Nagoya on the first weekend of August.