Inclusion Criteria:  Age >18 years. Lack of a contra-indication to a currently available COVID-19 vaccine. Diagnosis of MM according to International Myeloma Working Group (IWMG) criteria (Cohort 1) or Diagnosis of WM according to WHO criteria (Cohort 2)  For treatment naïve WM patients (Cohort 2A):  Patient must have no prior history of anticancer treatment for WM. The treating investigator must have no intention to initiate WM therapy within 2 months  For WM patients receiving BTK inhibitor (Cohort 2B):  Patient must have no history of cytotoxic chemotherapy within 1 year, and no history of other anticancer therapy within 6 months.  For currently or previously treated WM patients (Cohort 2C):  Patient must not be currently taking a BTK inhibitor or had recent exposure within 1 month of enrollment. Current or prior history of any other WM-directed therapy is allowed.  Exclusion Criteria:  -