The Agricultural Model Intercomparison and Improvement Project (AgMIP) coordinates protocol-based model intercomparison studies, analyzing model performance in order to build trust in models, identify deficiencies and strategies for model improvements, and to quantify model uncertainties. Within AgMIP, the Global Gridded Crop Model Intercomparison (GGCMI) focuses on global-scale crop model applications, development and evaluation. Several phases of GGCMI are conducted in coordination with the Intersectoral Impact Model Intercomparison (ISIMIP). In this special issue, we summarize protocol and experiment description papers, as well as model development and evaluation papers of the different GGCMI phases. Participation in GGCMI is voluntary and open to all groups that are able to conduct the minimum set of simulations. Different crops and management systems are included in the analyses, and output data are published in open repositories.