There is a need for a general framework for linguistic annotation that is flexible and extensible enough to accommodate different annotation types and different theoretical and practical approaches, while at the same time enabling their representation in a “pivot” format that can serve as the basis for comparative evaluation, merging, and the development of reusable editing and processing tools. To answer this need, we have developed a framework comprised of an abstract model for a variety of different annotation types (e.g., morpho-syntactic tagging, syntactic annotation, co-reference annotation, etc.), which can be instantiated in different ways depending on the annotator's approach and goals. The results have been incorporated into XCES (Ide, et al., 2000a), the XML instantiation of the Corpus Encoding Standard (Ide, 1998a,b), which provides a ready-made, standard encoding format together with a data architecture designed specifically for linguistically annotated corpora.