I teach a training class for people preparing to go on a short-term mission trip. Part of the training deals with cross-cultural encounters. Basically, the whole trip is a cross-cultural encounter. This is limited to an international trip, but can be encountered when going to another part of the US or even another part of the state.
As I am preparing for the next two sessions, I am reading two books: Serving With Eyes Wide Open by David Livermore and Revolutions in World Missions by K.P. Yohannan. These books help to explain why North Americans going on mission are too ethnocentric. We need to realize that the world does not revolve around us. You have to view a culture at face value, not through the filter of a North American.
Take for example a Croatian pastor. If you eat dinner with him, he will offer you wine. Most North American evangelicals (I am not comfortable with that term) would question the pastor's salvation. In Ireland, many Christians smoke and will go to the pub for a pint. Again, their salvation would be questioned. Just because a culture acts differently than us does not make it wrong.
Instead of looking at culture through our closed view, we need to look at how the people are hurting within their culture. We can't place our values on their culture, but we can discern where they are hurting and their needs within their cultures context. For example, two years ago I was in a certain area of Brazil. It was very poor, is it is in most of Brazil compared to our standards. The biggest need was a father figure for all the kids. We were in an area where there were a lot of single mothers. These kids latched on to the 6 younger team members (mainly between 25-50). Their need, culturally, was a male presence in their life. That became the focus of our time there. The reason to be there was building a church, but the ministry was to these kids. They needed us to share our lives. Through that, they were open to hearing of Christ's love.