Cultural barriers, a result of a lack of appreciation of cultural differences and the reasons behind different customs, bolster misunderstanding and conflict. One of the most solid cultural barriers is language. Ideological conflicts due to different economic, political, religious or social systems also divide cultures. Customs and traditions can vary so widely between cultures, that, for example, a gesture which would elicit a favourable response in one place may be considered insulting in another; consequently, many cross-cultural development programmes, having a "one-sided" design, are doomed to failure.
In every country where there has been immigration, there are likely to be cultural barriers between the original and the new population. Immigrants often react to discrimination and isolation by clinging to their former culture as a source of unity and strength, thus feeding the misunderstandings between the two groups.