We construct a method to evaluate the neighbourhood park vitality potential (NPV-potential), inspired by Jane Jacobs’s theory of urban and park vitality. The evaluation model produces an aggregate score of NPV-potential by combining information on the extrinsic factors of vitality, related to the park’s surrounding urban area, with evaluative judgements on the intrinsic factors, related to the park’s internal organisation and design. To showcase and submit the evaluation model to a preliminary test drive, we further present the results of an application on three parks in the city of Cagliari, Italy. The computed NPV-potential and the effective use of the three parks, obtained from direct observation, show a good degree of agreement. While far from a robust validation, which would require more extensive empirical studies with larger and more internally variable samples of parks, the reported agreement between the potential and the observed vitality on the ground is a preliminary indication of the possible usefulness of the proposed evaluation method for urban planning and design.