As a temp/contractor, its hard to get to know people in an organisation when they know you'll only be there for a week, you might have lunch with the team one or two days, but for the most part, you'll spend a lot of your time on your own.
In larger companies (I primarily work in IT environments) that are more diverse (in Australia anyway), ethnic groups stick together and speak in their native tongues. I've sat and watched a group of Indian guys/girls chat in hindi in a circle over lunch, a bunch of Chinese guys sit and chat in Mandarin while a table full of Japanese people do the same a few meters away and the two white guys (who I don't know/haven't been introduced to) sit and don't talk. What's more, no-one interacted with anyone else at all outside of their little groups.
I personally find that really bizarre and I wish i could change it somehow but as i'm not even involved with the organisation other than as a contractor, its quite removed from my role.