Introduction: The concept of monoclonal gammopathies (GM) is widely known in medical literature and refers to the typical finding of a monoclonal spike in the gamma region on serum protein electrophoresis. Multiple myeloma (MM) is by far the most representative entity within the group and is the second most frequent cause of hematological malignancy. Objective: To review the main clinical characteristics of monoclonal gammopathies, with emphasis on multiple myeloma. Methods: Text written based on the magistral conference with the same title presented at the ACMI Valle - Universidad Libre Internal Medicine Congress. Results: these multiple myeloma topics are discussed: history, pathophysiology, epidemiology, clinical scenarios for suspection, diagnosis, risk stratification and treatment; also we briefly discuss about other plasma cell neoplasms associated with multiple myeloma (light chain amyloidosis, Waldeström's macroglobulinemia, POEMS syndrome). Conclusion: Multiple myeloma is the most representative entity within the group of monoclonal gammopathies and in general is the second most common cause of hematological malignancy; to know the main clinical characteristics of these pathologies and the clinical scenarios in which they should be suspected is essential to achieve an early diagnosis that favors better outcomes.