The objective of this research project was to investigate candidate damage tolerance test methodologies for sandwich composites and to propose specific methodologies and configurations for standardization. Three candidate test configurations are currently under evaluation. The first methodology utilizes an end-loaded Compression After Impact (CAI) test configuration. Initial evaluations have been performed using sandwich configurations with both carbon/epoxy and glass/epoxy facesheets and Nomex honeycomb core. Research has focused on establishing the required specimen size to prevent interactions between the damage present and the boundary conditions during loading as well as special requirements to promote proper alignment and end loading for a variety of sandwich configurations. Second, a four-point flexure test methodology has been identified for evaluating post-impact performance. The composite sandwich panel may be oriented such that the damaged facesheet is loaded in compression or tension. Similar to the CAI test configuration, research has focused on the required size of the gage section between the inner loading points as well as additional sandwich panel requirements to prevent outer-span core shear as well as loading-point compression failures. The third candidate methodolgy, the “hydromat” test configuration, utilizes a water-filled bladder to apply a distributed load to the surface of the composite sandwich panel while supporting the panel along its edges. Initial evaluation using composite sandwich panels with carbon/epoxy and glass/epoxy facesheets and Nomex honeycomb core has exposed difficulties when using this test configuration for assessing strength reductions associated with damage. All three candidate test methodologies are being examined for their limits of applicability and to establish recommended testing procedures. Expected benefits to aviation include standardized test methodologies for use in assessing the damage tolerance of sandwich composites used in aircraft structures.