This chapter examines the sensitization potential of marine shellfish proteins and strategies for managing them. Initially, the mechanisms of food-allergic reactions, including IgE-mediated rapid and delayed hypersensitivity reactions, are presented. Subsequently, this section addresses the epidemiology and clinical manifestations of allergic reactions to marine shellfish and provides an overview of the most common allergenic proteins found in shellfish, including promyosin, arginine kinase, and myosin light chain, along with a description of their biological properties. Furthermore, a range of methodologies for the detection of shellfish allergens are presented, including ELISA, immunoblotting, biosensors, mass spectrometry, and others. Finally, this section will discuss the allergenicity control methods that can be applied to marine shellfish proteins. These include thermal processing treatments, biochemical methods (e.g., glycosylation, enzymolysis, and fermentation), and novel processing methods (e.g., ultrasound, irradiation, and pulsed UV).