The purpose of scientific illustration is not to create art, but to document science. Previous experience with medical illustration highlights the importance of communication between the scientist and the artist. Communication at this level involves the observers' eyes and mutual trust. Scientific illustration requires the development of both technology and the power of nature inherent in man. The observers' eyes might demonstrate greater influence than the imagination. It is time to make a lasting connection between the observational skills of the artist and of the scientist. The permanent value and lasting significance of scientific illustration occur when the objective observational skills of both disciplines can contribute equally, even if the details to which they are drawn differ.