I am using Header Context Filter Menu for the RadGrid.I found the two different filter options with that but there is an "And" option where "Or" option makes more sense to use with compare to "And".Even I did not finding any option on RadGrid to change this "And" option to "Or". Waiting for you kind response if you have any work arround or fix for this as i am in b/w of the development and found this. So let me know as early as possible.