During the past two decades, the enemy´s ability to perform threat detection, classification, and targeting has improved significantly due to the advent of low-cost, more-capable electronic circuitry, computational resources, and sensor technologies. Consequently, the risk to Navy combatants has appreciably increased. It is imperative that the Navy has a strategy to counter current and anticipated future improvements in threat technologies. The underwater signature project have during the last two years been focusing on (i) expanding the knowledge of basic physics required to understand and control surface ship and submarine acoustic and non-acoustic signatures; (ii) Improve the physics-based modeling and simulation approaches to support the understanding and mitigation of electric and magnetic fields associated with naval platforms; and (iii) to initiate studies leading to understand correlations between different types of signatures, their generation and possible reduction.