We will investigate the clinical manifestations and molecular genetic defects of heritable connective tissue disorders, concentrating on the Marfan, Stickler, and Ehlers-Danlos syndromes. Although each of these conditions has been known for many years, the full spectrum of the associated phenotypes continues to be expanded and the genetic etiology of these conditions has not been completely elucidated. In addition, many patients have features overlapping two or more of the described syndromes, precluding unequivocal diagnosis. The goals of this study are to further define and characterize the full phenotype and natural history of these disorders, and to perform genetic linkage, gene identification, mutation detection, and genotype/phenotype correlations in affected individuals and families. Individuals suspected to have Marfan, Stickler or Ehlers-Danlos syndrome or a closely related disorder, as well as interested family members, will be enrolled. Participants will undergo genetic analyses and periodic clinical assessment. The expected outcomes will be improved clinical descriptions of the conditions and gene and mutation identification with analysis of genotype/phenotype correlations.