The development of new technologies now allow scientists to investigate the molecular basis and clinical manifestations of monoclonal B cell lymphocytosis (MBL), chronic lymphocytic leukemia(CLL)/small lymphocytic lymphoma (SLL), lymphoplasmacytic lymphoma (LPL)/Waldenstrom macroglobulinemia (WM), and splenic marginal zone lymphoma (SMZL). Applying these methods in a natural history study can clarify processes involved in disease progression and possibly lead to the discovery or validation of treatment targets.