Group Stage - October 5th - October 10th, 2017
Four teams from Play-In Stage 2 join twelve teams with direct entry from Korea, China, Europe, TW/HK/MO, North America, and Southeast Asia.
All sixteen teams are divided into four groups where they play a Double Round Robin format.
All Matches are played in a Bo1.
The top two teams in each group advance to the Knockout Stage.
The remaining teams are eliminated.
Knockout Stage - October 19th - November 4th, 2017
Eight teams play in a single elimination bracket over seven days.
All matches are Bo5.
See this Update from the 2016 edition:
http://www.lolesports.com/en_US/articles/2017-world-championship-update