The three services have prepared a Joint Integrated Avionics Plan which proposes to utilize as much common architecture as feasible. Inherent in this project is the requirement to address integrated Diagnostics (ID). The National Security Industrial Association (NSIA) Integrated Diagnostics Working Group (IDWG) has been reviewing these documents and working closely with the Joint Services Group to provide consensus for integration of all factors affecting fielding of ID for advanced avionics architectures (AAAs). AAAs and expert system concepts capable of diagnosing system faults call for total integration of the embedded and support diagnostics. The main challenge of integrated avionics (IA) systems designers is to anticipate and understand the ID product requirements, factor these into the designs, and monitor compliance with the requirements as the product moves through various stages of development, production, and operational use.This paper reviews AAAs, issues associated with testability/ID, preventive maintenance (I'M) integration with ID. and emerging technologies required for an effective demonstration of ID for AAAs.