--This special session will explore developments in the detection, state estimation, classification, and threat identification of entities represented by or embedded in a network. Problems of interest include detecting and identifying groups and links between members of groups. These groups may be static or dynamic. At other times the entity of interest may be represented by a set of nodes and links embedded in a larger network. Also included is the problem of determining the state of a system that is represented by the joint status of a network of linked nodes. Applications of this technology include detecting, identifying, and tracking groups or networks of interest and estimating the state of development of projects of interest from indirect observations.