Are people possessed by demons today? What is the modern Christian perspective?

In the three gospels of Matthew, Mark, and Luke, Jesus repeatedly casts out demons , speaks to them , etc. He tells his disciples to do the same. There are so many references it would be difficult to put them all here. This is not a topic that is very frequently mentioned (if at all) in my experience in the modern church (here in the USA at least). But reading the New Testament it cannot be easily glossed over. What is the church's view on demonic possession today, especially in light of modern psychology and drug therapy? Where people possessed by demons in ancient times but not today? Are people with certain types of psychological disorders (or in certain times/cases) actually possessed?