The Dutchman will begin a three-year contract at Old Trafford after the conclusion of his work in charge of Netherlands at the World Cup.Frans Hoek and Marcel Bout, countrymen of the new boss, also arrive at Old Trafford as coaches, with the former specialising in goalkeeping and the latter in scouting the opposition."In Louis van Gaal, we have secured the services of one of the outstanding managers in the game today," United's chief executive, Ed Woodward, said in a statement."He has achieved many things in his career to date and Old Trafford provides him with a fitting stage on which to write new chapters in the Manchester United story."Everyone is very excited about this new phase in the club's history. His track record of success in winning leagues and cups across Europe throughout his career makes him the perfect choice for us."Van Gaal himself declared: "To work as a manager for Manchester United, the biggest club in the world, makes me very proud."This club has big ambitions; I too have big ambitions. Together I'm sure we will make history."