We formulated a model of visual search by conducting a work flow study and task analysis of art directors as they searched for images to use in an advertisement. The analysis revealed the presence of artistic and image concepts, flexible structures which guide the search and are molded by them. Analysis results were used to build a model-based interface for visual search. Results from presenting the interface to users indicate that the interface has the potential to make significant contributions to the visual search task, both in time savings and as an aid to the creative process.