To identify families which include two or more brothers and/or sisters who manifest Unipolar Depression, Recurrent.  Participating family members will be paid for their time and travel

To conduct direct diagnostic and family history interviews that will provide the clinical, social, and biographical history needed to study the genetics of Unipolar Depression, Recurrent

To maintain confidentiality of all diagnostic and genetic information obtained from research participants

To conduct linkage studies to identify the specific chromosomal regions that are likely to contain the gene(s) that modify the risk of developing Unipolar Depression