The book " L - glutaminase production by marine fungi, authored by Dr. Sabu Abdulhameed and Prof. (Dr.) M Chandrasekaran is an authentic record on the bioprocess design and development for the production of the therapeutically and industrially important biocatalyst, L - Glutaminase. The book narrates various aspects of bioprocess development including Submerged fermentation, Solid state fermentation and Immobilization. Utilization of cheap agro-residues for the production of this important enzyme adds quality to the work. Any technology development for the future should prove itself as eco-friendly for its acceptability and viability. The achievement of multi fold enhancement in the yield of L-glutaminase after bioprocess optimization shows the strength of fermentation technology. The authors are renowned experts in the field of bioprocess technology and contributed thoroughly to this re-emerging field.