first and foremost
Also, first of all. Most important, primarily; also, to begin with. For example, First and foremost, I want to thank our sponsors, or What we need, first and foremost, is a new secretary, or We have to deal, first of all, with the early history. The first term, dating from the late 1300s, is redundant, since first and foremost mean virtually the same thing. Both it and the variant, which dates from the mid-1500s, are used to give emphasis to the initial item in a list of several. Also see first off; first thing.
Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.