Walter Avarelli (3 June 1912 – 1987)^[1] was an Italian bridge player, a member of the famous Blue Team, with whom he won nine Bermuda Bowls and three World Team Olympiads from 1956 to 1972.

Avarelli was born in Rome and became a judge there.^[1] He first took up rudimentary bridge during World War II when more than thirty years old.^[2] Along with interests in tennis, riding and motor racing, he was especially noted for "his addiction to gastronomy".^[2]

Avarelli was the longtime partner of Giorgio Belladonna using the Roman Club bidding system. They improved the system together and presented it in a book that was published in at least two Italian editions, 1958 and 1969.

• Il sistema fiori romano, Giorgio Belladonna and Walter Avarelli (1958), 163 pp.; 3rd edition (Bridge d'oggi, 1969), 181 pp., OCLC 220620707
• The Roman Club System of Distributional Bidding, Giorgio Belladonna and Walter Avarelli (Simon & Schuster, 1959; Cassell, 1960)

World championships

Avarelli won 12 world championships, all as one of six players on the Italy open team-of-four.

• Bermuda Bowl (9) 1957, 1958, 1959, 1961, 1962, 1965, 1966, 1967, 1969
• World Team Olympiad (3) 1964, 1968, 1972

Runners-up: none. He joined the Italy team after its second-place finish in the 1951 Bermuda Bowl and retired before its double second-place finish in 1976.

European championships

• European Open Teams (4) 1956, 1957, 1958, 1959

• Belladonna, Giorgio and Giorgio Manca (1955), Il sistema Manca: Fiori romano [The Manca system: Roman Club], OCLC 468328163.
• Belladonna, Giorgio (1958), Il Nuovo Fiori Romano.
• Belladonna, Giorgio (1977), Il Nuovissimo Fiori Romano.
• Belladonna, Giorgio and Benito Garozzo (1986), Il Moderno Fiori Romano.

• "International record for Walter Avarelli". World Bridge Federation.