As of today (21st November 2016) Dragonair is officially Cathay Dragon. Cathay Pacific had always owned and operated small various parts of the airline, and now they completely own them.
Together the two carriers will fly up to 180 different countries with Cathay Pacific mainly doing more international and long-haul travel whereas Cathay Dragon focuses on mainland China routes.
The two airlines will utilize their Hong Kong hub for easy connections around the world. Cathay Dragon will also use Cathay’s lounges, and they also use the same frequent flyer program ”Marco Polo”.
Cathay Dragon operates a fleet of 15 A320’s with, and without business class, 8 A321 aircraft in an all-economy layout and 19 A330’s with business and even some first class. (Cathay Dragon first class is the same as Cathay Pacific Business class)
Cathay Pacific even made a video about the two carriers: