における and において are the more formal written versions of での and で, respectively. They can only take the place of で when the particle is used to mean a “place of action” or a specific context. In other words, they cannot be used to mean “by means of” (such as a mode of transport or a tool). Therefore, the following is incorrect:
自転車において通勤しています。(✘)
I commute to work by bicycle.
Noun vs. Verb Modifiers
A major testing point on Japanese exams is knowing which form to use. Because における acts like での, it must be followed directly by a Noun. Because において acts like で, it modifies the Verb (the action) in the sentence.
中東における政治的不安。
Political unrest in the Middle East. (における modifies the noun 不安).
経済における市場の役割が重要である。
The role of the market in the economy is important. (における modifies the noun 役割).
国会においては社会福祉の方針変更に関する提案を議論する予定です。
The proposal regarding policy change for social welfare is scheduled for debate in parliament. (において modifies the action 議論する).
Abstract Places (Time & Fields)
While often used for physical locations, these grammar points are frequently used to express an abstract “place,” such as an era in time, a field of study, or a specific situation.
現代の医学分野において、AIの技術は欠かせない。
In the field of modern medicine, AI technology is indispensable.
Formality & Naturalness
における and において are highly formal and would typically be seen in news broadcasts, essays, or academic writing. It would be incredibly unnatural to use them in place of で for simple, everyday sentences.