Cross-points are central for any fieldwork on binational couples (or mixed marriages). Starting from a comparison of two informants' networks in Bern and Neuch?tel we analyse their construction, anchorage or tension points (family ties and bonds of friendship, integration into the world of work, lay or religious associative steps, geographic situation of ??ethnic?? shops). In the perspective of a ??multi-sited ethnography?? we concentrate on fieldwork conditions implying both proximity or exoticism within the framework of an ethnology faced with political problems raised by migrations in a contemporaneous multicultural society.