Happel is regarded as one of the greatest managers of all-time, winning both league and domestic cup titles in the Netherlands, Belgium, West Germany, and Austria. Happel won the European Cup twice, in 1970 with Feijenoord and 1983 with Hamburger SV, managed Club Brugge to a European Cup runner-up finish in 1978, and won a runners-up medal with the Netherlands at the 1978 FIFA World Cup. He was the first of the five managers to have won the European Cup with two clubs (Carlo Ancelotti, Ottmar Hitzfeld, José Mourinho, and Jupp Heynckes being the other four). He is also one of six managers–– along with Ancelotti, Mourinho, Giovanni Trapattoni, Tomislav Ivić, and Eric Gerets–– to have won top-flight domestic league championships in at least four different countries.