From the abstract: "We present a data literacy maturity model (DLMM) that was developed in the context of non-governmental organizations (NGOs). Based on the development of a preliminary maturity model, action design research (ADR) is used to develop the model throughout three iteration phases. The main contribution is a data literacy maturity grid that describes 11 data literacy competencies on four competence levels that is complemented by a self-assessment tool. The proposed maturity model should enhance the understanding of the required skills that are needed to kick off data projects, identify strengths and gaps, and thus empower to plan future data practices in accordance with predefined goals.