Erythromelalgia is characterized by spontaneous recurrent episodes of redness, heat, and pain of the extremities that can be triggered or worsened by heat. Raynaud's phenomenon occurs in response to cold exposure and presents as pallor of the fingers or toes, often followed by cyanosis and rubor. Although the 2 conditions may appear to be opposites in symptomatology and clinical presentation, there are very rare reports of their coexistence. A case of coexistent erythromelalgia and Raynaud's phenomenon is presented. The pathophysiology is reviewed to elucidate a common mechanism underlying some cases of the 2 seemingly opposite conditions. A review of the literature indicates that causative and pathophysiologic similarities between the 2 conditions may exist in some cases. Rare reports of coexistence of the 2 disease processes further strengthen such research findings.