Existing computer technologies poorly support the ideation phase common to graphic design practice. Finding and indexing visual material to assist the process of ideation often fall on the designer, leading to user experiences that are less than ideal. To inform development of computer systems to assist graphic designers in the ideation phase of the design process, we conducted interviews with 15 professional graphic designers about their design process and visual information needs. Based on the study, we propose a set of requirements for an ideation-support system for graphic design.