A Study of Real-Life Current Standards of Care in Participants With Relapsed and/or Refractory Multiple Myeloma

Inclusion Criteria:

* For Period 1 and 2: Have a documented diagnosis of multiple myeloma according to International myeloma working group (IMWG) diagnostic criteria. For Period 3: Start of talquetamab for the treatment of a documented diagnosis of relapsed and/or refractory multiple myeloma (RRMM) according to IMWG diagnostic criteria and the approved indication. The decision to start talquetamab must be made independently of the decision to participate in the study, with the start of treatment occurring up to 28 days following the start of screening or having occurred up to 21 days before the informed consent form (ICF) date
* For Period 1 and 2: Have an Eastern Cooperative Oncology Group (ECOG) Performance Status grade of 0 or 1. For Period 3: Have ECOG performance status of 0,1 or 2
* For Period 1,2 and 3: Must not be pregnant or must not plan to become pregnant within the study period
* For Period 1,2 and 3: Participants must sign an ICF indicating that he or she understands the purpose and observational nature of the study and is willing to participate. Consent is to be obtained prior to the initiation of any study-related data collection
* For Period 1 and 2: Received at least 3 prior lines of therapy (induction with or without hematopoietic stem cell transplant and with or without maintenance therapy is considered a single regimen). Undergone at least 1 complete cycle of treatment for each line of therapy, unless progressive disease (PD) was the best response to the line of therapy
* For Period 1 and 2: Must have documented evidence of progressive disease based on participating physician's determination of response by the IMWG response criteria on or after the last regimen. Participants with documented evidence of progressive disease within the previous 6 months and who are refractory or non-responsive to their most recent line of treatment afterwards are also eligible
* For Period 1 and 2: Measurable disease at screening as defined by any of the following: Serum monoclonal paraprotein (M-protein) level 1.0 g/dL or urine M-protein level 200 mg/24 hours; or Light chain multiple myeloma without measurable disease in the serum or the urine: Serum immunoglobulin free light chain 10 mg/dL and abnormal serum immunoglobulin kappa lambda free light chain ratio
* Period 1: Received as part of previous therapy a PI, an IMiD, and an anti-CD38 antibody (prior exposure can be from different monotherapy or combination regimens)
* Period 2: Received as part of previous therapy a PI, an IMiD, an anti-CD38 antibody, and BCMA-targeted therapy (prior exposure can be from different monotherapy or combination regimens)
* For period 3: At least one of the following prior to the start of talquetamab: a. Measurable disease at screening as defined by any of the following: Serum monoclonal paraprotein (M-protein) level greater than or equal to (\>=) 0.5 grams per deciliter (g/dL) or urine M-protein level \>= 200 milligram (mg) /24 hours; or b. serum immunoglobulin free light chain \>= 10 milligrams per deciliter (mg/dL) and abnormal ratio of involved and uninvolved free light chains or c. presence of bone lesions or plasmacytomas (\>=1 lesion has 2 diameters \>= 1 centimeter \[cm\])