Effective communication is vital to successful teamwork; realistic communications ("comms") in training are substantially easier to provide than realistic simulations of many other (sub)systems, and are readily captured electronically. However, theory and practice in assessing communications have not kept pace with assessing other aspects of performance, with the growing importance of communication, or with the power of methods to collect and manipulate comms data. Communication assessment can be applied at multiple levels, from how much trainees adhere to specific protocols (e.g., for vocabulary, syntax, rules of reply) to abstract questions like the extent to which they engage in effective back-up behavior. Useful comms assessment requires careful specification of the questions to be addressed and the measures used to address them, not simply collecting all comms and applying powerful methods. This paper is grounded in the application of several communication analysis techniques during a 2008 Air and Space Operations Center week-long training experiment run by the Air Force Research Laboratory with active duty Air Force personnel. It provides a framework for comms assessment and will lead to practical steps to enhance performance assessment by analyzing communication. We discuss preliminary findings based on applying these techniques to chat data from this exercise, relate them to changes in performance over the week of training, and consider them in the larger context of how comms assessment can add value. We describe several visualization tools to explore these rich data so researchers and instructors can better understand what comms analysis can tell us. We argue that intensive involvement of potential users and domain SMEs is vital both during development of communication assessment approaches and to assess the assessments, as it were, so that the state of the art and its scientific basis can both develop rapidly.