 The Rare Lung Disease Consortium RLDC, a group of geographically-dispersed clinical research sites, has been established to conduct collaborative clinical research regarding rare lung diseases. The collaborative work includes diagnostic, therapeutic and other studies in patients with pulmonary alveolar proteinosis PAP, lymphangioleiomyomatosis LAM, alpha-1 antitrypsin deficiency AATD, or hereditary interstitial lung diseases. These patients can have delayed or incorrect diagnoses, and sub-optimal clinical management. The present protocol is focused to individuals with PAP. 