Cross-cultural communication (also frequently referred to as intercultural communication, which is also used in a different sense, though) is a field of study that looks at how people from differing cultural backgrounds communicate, in simlar and different ways among themselves , and how they endeavour to communicate across cultures.

http://en.wikipedia.org/wiki/Cross-cultural_communication

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Intercultural Communication is sometimes used synonymously with cross-cultural communication. In this sense it seeks to understand how people from different countries and cultures act, communicate and perceive the world around them. As a separate notion, it studies situations where people from different cultural backgrounds interact. Intercultural communication plays a role in anthropology, cultural studies, linguistics, psychology and communication studies.

http://en.wikipedia.org/wiki/Intercultural_communication