Digital transformation is a complex yet indispensable endeavor for SMEs. Hence, SMEs initiate and implement digital innovation projects to drive their digital transformation but face difficulties in the initiation phase, which could lead them to embark on projects with little value. As a remedy, SMEs may collaborate with external digital innovation units to support their project initiations. However, underlying project characteristics are often poorly understood, so much so that initiations often happen ad hoc. The research goal of this article is to develop a taxonomy that supports the initiation of digital innovation projects in SMEs in collaboration with external digital innovation units. The taxonomy development combines both conceptual and empirical perspectives. The former is informed by a structured literature review. The latter emerges from analyzing 210 project reports of German SMEs. The resulting taxonomy comprises 10 dimensions and 30 characteristics. Based on the taxonomy and the analyzed projects, 5 project types are derived by using cluster analysis methods. External digital innovation units can use the taxonomy and the 5 project types to classify and better understand digital innovation projects in SMEs. The article contributes to the body of knowledge and facilitates future research on digital innovation projects in SMEs.

对于中小企业来说，数字化转型是一项复杂但不可或缺的努力。因此，中小企业发起并实施数字创新项目来推动数字化转型，但在启动阶段面临困难，这可能导致他们开展价值不大的项目。作为补救措施，中小企业可以与外部数字创新单位合作，支持他们的项目启动。然而，人们往往对项目的基本特征知之甚少，以至于项目的启动常常是临时发生的。本文的研究目标是开发一种分类法，支持中小企业与外部数字创新单位合作启动数字创新项目。分类学的发展结合了概念和经验的观点。前者是通过结构化文献综述获得的。后者是通过分析德国中小企业的 210 个项目报告得出的。由此产生的分类包含 10 个维度和 30 个特征。根据分类和分析的项目，利用聚类分析方法得出5个项目类型。外部数字创新单位可以使用分类法和5种项目类型对中小企业的数字创新项目进行分类和更好地理解。本文对知识体系做出了贡献，并促进了中小企业数字创新项目的未来研究。