According to the h-index, a method for ranking scientists based on the number of papers they publish and citations they receive, Foster ranks third with a score of 67. Featured in the August 16 issue ofNature, the h-index indicates the number of papers a particular author publishes that receive at least that same number of citations; thus, Ian Foster's score of 67 means that he has published 67 papers that have received at least 67 citations apiece. The world's leading computer scientist, by this scale, has a score of 70.

"It's nice to realize that when I write papers people will read them, and that I have some influence", Ian Foster stated. "Presumably, my score represents the broad interest in my field."

However, Ian Foster's modesty prevented him from assigning a great deal of weight to the h-index. "I think it says a little more about the limitations of these numerical scores than anything", he stated of his ranking. "It's a pluralist way of defining a scientist's reputation, while the more commonly-used mechanism for that is to rely on the opinions of other experts in the field. But numbers can serve some purpose as another way of evaluating things."

Ian Foster currently works as the director of the Computation Institute, a joint project between Argonne and the University of Chicago.