Played for both clubs:
Billy Thirlaway Birmingham 1926-27 Cardiff 1926-30
Ernie Curtis Cardiff 1926-28/33-34 Birmingham 1927-34
Stan Davies Birmingham 1927-28 Cardiff 1928-29
Harry Riley Birmingham 1928-29 Cardiff 1934-36
Reginald Keating Birmingham 1931-32 Cardiff 1933-36
Len Evans Cardiff 1930-33 Birmingham 1933-34
Ernest Sykes Birmingham 1936-39 Cardiff 1939-40
George Edwards Birmingham 1946-49 Cardiff 1948-55
Greg Farrell Birmingham 1962-64 Cardiff 1963-67
Johnny Vincent Birmingham 1963-71 Cardiff 1972-75
George Johnston Cardiff 1964-67 Birmingham1969-70
George Smith Birmingham 1970-73 Cardiff 1973-75
Alan Campbell Birmingham 1970-76 Cardiff 1975-81
Bob Hatton Birmingham 1971-76 Cardiff 1982-83
Steve Lynex Birmingham 1978-81/86-87 Cardiff 1988-90
Tony Evans Cardiff 1975-79 Birmingham 1979-83
Kevin Summerfield Birmingham 1982-83 Cardiff 1984-85
Nicky Platnauer Birmingham 1984-86 Cardiff 1986-89
Billy Ronson Cardiff 1979-82 Birmingham 1985-86
Roger Hansbury Birmingham 1986-90 Cardiff 1989-92
Martin Thomas Cardiff 1982-83 Birmingham 1988-93
Ian Rodgerson Cardiff 1988-91/95-97 Birmingham 1990-93
Andy Saville Birmingham 1992-95 Cardiff 1997-99
Keith Downing Birmingham 1993-94 Cardiff 1995-96
Paul Harding Birmingham 1993-95 Cardiff 1995-96
Danny Hill Birmingham 1995-96 Cardiff 1997-2001
John Cornforth Birmingham 1995-96 Cardiff 1999-2000
Jason Bowen Birmingham 1995-97 Cardiff 1998-2004
Andy Legg Birmingham 1995-97 Cardiff 1998-2003
Eddie Newton Cardiff 1991-92 Birmingham 1999-2000
Steve Jenkins Birmingham 2000-01 Cardiff 2002-03
Darren Purse Birmingham 1998-2004 Cardiff 2005-present
Cameron Jerome Cardiff 2004-06 Birmingham 2006-present