に当(あ)たってWhen, When doing something, On the occasion, At the time

に当(あ)たり or に当(あ)たって is a formal grammar pattern in Japanese used to convey the meaning of 'at the time of (A)', 'when doing (A)', or 'on the occasion of (A)'. Like に際(さい)して 'on the occasion of (A)', it will often be used in regard to preparation for future events. This structure is a combination of に, and the う-Verb 当(あ)たる 'to hit', or 'to come into contact' in either its formal-conjunctive form or て-form.

に当(あ)たり will appear following verbs in their dictionary form, or nouns. There are two primary nuances that this structure will be used for, so let's look at a few examples of each.

The first is when (A) is some sort of special occasion or condition from which (B) will be done.

The second is when (A) is some sort of goal or target for which (B) will be the means or measures in response to that goal.

Caution

Unlike に際(さい)して, which can be used for either positive or negative situations, に当(あ)たり will primarily only be used for positive or neutral situations.