A formal expression meaning 'on the occasion of' or 'at the time of', used for significant or special events rather than everyday occurrences. It marks the moment just before or during an important event and often introduces remarks, precautions, or actions appropriate to that occasion. に際し is the stiffer written form.
[Noun / Verb-dictionary] + に際して/に際し
開会に際して、一言ご挨拶申し上げます。
Kaikai ni saishite, hitokoto goaisatsu moushiagemasu.
On the occasion of the opening, I would like to say a few words.
開会に際して marks the formal opening as the moment for the greeting.
契約に際して、注意すべき点を説明します。
Keiyaku ni saishite, chuui subeki ten wo setsumei shimasu.
At the time of signing the contract, I will explain the points to note.
契約に際して introduces precautions relevant to the contract occasion.
留学するに際し、多くの人にお世話になった。
Ryuugaku suru ni saishi, ooku no hito ni osewa ni natta.
On the occasion of studying abroad, I was indebted to many people.
Verb-dictionary + に際し marks the special event of going to study abroad.
• Register: quite formal; used for weddings, contracts, ceremonies, departures. • Reserved for notable events — not for routine daily actions. • に際し (without て) is the stiffer, written variant.
The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones に際して is tested against.
にあたって is very close ('on the occasion of, in preparation for') and slightly less stiff; に際して emphasizes the specific timing of a formal event.
時に simply marks 'when / at the time', for any everyday moment; に際して is formal and reserved for significant, special occasions.
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