Diagnosis of fibromyalgia (FM) remains controversial even though diverse diagnostic criteria have been developed. This review looks at the history, evolution of diagnostic criteria, endless controversy, recent trends and future perspectives regarding FM diagnosis. Some have criticized that diagnosis of FM could lead to medicalization, whereas others have raised concerns of under-diagnosing FM. With the evolution of diagnosis criteria from American College of Rheumatology 1990 to modified American College of Rheumatology 2010, diagnosis of FM has become simpler. The recent trend of applying patient-reported questionnaires has also increased a simpler FM diagnosis. Reliable biomarkers will not be available for the foreseeable future, so diverse assessment tools will have to be used more pro-actively. After initial diagnosis, multiple and comprehensive assessment measures are needed during the course of treatment in order to better understand type and severity of FM symptoms. These, in turn, could help classify FM based on symptom domain, symptom severity, and comorbidity which would enable more personalized treatment.