Casein is a protein that is found in milk and used independently in many foods as a binding agent. Presently, there are numerous applications of casein such as coatings, adhesive, as a paper packaging material, in the leather, textile, and food industries. In this review we describe the use of casein as a building block for the fabrication of proteinaceous microspheres (PM) and film materials. Casein can be used as an interface material holding stable microsphere emulsions made from water and hydrophobic solvents, as well it can be used as matrix material for producing stable films for medical applications. The current manuscript will attempt to review the experiments that have been conducted for the production of microsphere emulsions and the encapsulation of drugs inside the casein spheres. Moreover, the paper will describe the chemical modifications of the casein protein made with the bifunctional compound, glutaraldehyde. © 2012 Nova Science Publishers, Inc. All rights reserved.