Are sex or gender crucial components of modern marriage? In Bellinger v. Bellinger [2001] EWCA Civ 1140, [2001] 2 F.L.R. 1048, the Court of Appeal returned to the question of the relevance of biological sex to the validity of marriage, first considered thirty years ago by Ormrod J. in Corbett v. Corbett (otherwise Ashley) [1971] P. 83. Both cases involved male-to-female transsexuals who had undergone gender reassignment surgery but in Bellinger, Mrs. Bellinger sought a declaration under section 55 of the Family Law Act 1986 that her marriage to Mr. Bellinger was valid at its inception and still subsisting (unlike Corbett, which involved a nullity petition). The Court, by a majority, upheld the decision of Johnson J. refusing the declaration.