Katarzyna Rycerz A Support for HLA-based Iteractive Simulations on the Grid This talk presents the analysis, design and feasibility study of a system that supports execution of High Level Architecture (HLA) distributed interactive simulations in the Grid environment. The architecture of the system is based on the Open Grid Services Architecture (OGSA) concept that allows for modularity and compatibility with Grid Services. The system enables the control of simulation execution through Grid Service interfaces as well as the internal control and data flow through HLA. The design supports migration of federates of HLA applications due to changing grid conditions and monitoring of their performance.