Voice networks which support military operations require multi-level precedence based communications to ensure that critical voice calls and messages arrive at their destination, even at the expense of lower precedence calls. Multi-Level Precedence and Preemption (MLPP) is straight-forward to implement in circuit-switched systems, but military forces have now embraced the transition to converged IP networks. Given this transition, there is a requirement for the future US, NATO, and coalition networks to support precedence for both real-time/inelastic and elastic applications over an infrastructure incorporating an IPsec encrypted, cipher-text network core, over both fixed and disadvantaged networks. Authentication and authorization mechanisms must be provided that ensure only properly authorized users are permitted to use particular precedence levels. Particular challenges include: the impact of encryption on the call signaling; supporting voice calls over disadvantaged transmission links; achieving precedence for elastic traffic; and the planning, monitoring, and management across a Federation of Systems. This paper summarizes the issues and considers the solution space.