The concepts "innovators" and "opinion leaders" are central to diffusion theory. There are many issues under discussion considering the concepts of innovators and opinion leaders. One of the most important issues is whether innovators and opinion leaders overlap across innovation categories or not. This subject is more generally mentioned as the overlap of, innovativeness and opinion leadership across innovation categories. Does a person with a high (low) innovativeness in one category have a high (low) innovativeness in another category ? Does a person with a high (low) opinion leadership in one category have a high (low) opinion leadership in another category ? In this article, these questions were discussed. At least for the respondents studied in this case, the foliowing may be said. There are generalized innovators who are innovators in many categories. As for innovator overlap across categories, for all combination of categories, actual overlap was more than the expected figure. As for consistency of innovativeness, a strong correlation was observed in several pairs. There are generalized opinion leaders who are opinion leaders in many categories. As for opinion leader overlap across categories, for most of all combinations of categories, actual overlap was more than expected figure. As for consitency of opinion leadership, a strong correlation was obseved in a few pairs.