expression
on the occasion of; at the time of; when
A formal expression used for an action or situation connected with a particular event, occasion, or important step. It commonly follows nouns, as in ご利用に際して, or dictionary-form verbs, as in 契約を結ぶに際して.
ご利用に際しては、利用規約をお読みください。
When using the service, please read the terms of use.
契約を結ぶに際して、いくつか確認したい点があります。
When entering into the contract, there are a few points I would like to confirm.