The article analyses cross‐border small‐scale trading (CBST) from the perspective of New Institutional Economics. It offers an alternative analytical starting point to this topic, which is mainly tackled by sociologists and anthropologists. It is argued that concepts like social capital or social embeddedness can be of certain analytical use but that they hardly suffice to explain human behaviour in a detailed manner. The case of reference is the institution of bribery as it evolved in the first half of the 1990s at the Bulgarian‐Turkish border.