The 2017 Shared Task on Extrinsic Parser Evaluation (EPE 2017) seeks to provide better estimates of the relative utility of different types of dependency representations for a variety of downstream applications that depend heavily on the analysis of grammatical structure. EPE 2017 defines a generalized notion of lexicalized syntactico-semantic dependency representations and provides a common interchange format to three state-of-the-art downstream applications, viz. biomedical event extraction, negation resolution, and fine-grained opinion analysis. As a first step towards building a generic and extensible infrastructure for extrinsic parser evaluation, downstream applications have been generalized to support a broad range of diverse dependency representations (including divergent sentence and token boundaries) and to allow fully automated re-training and evaluation for a specific collection of parser outputs. Nine teams participated in EPE 2017, submitting 49 distinct runs that encompass many different families of dependency representations, distinct approaches to pre-processing and parsing, and various types and volumes of training data.