While I believe that there is intelligent alien life in the universe, I do not believe that we will find in our galaxy, the Milky Way.
The odds are very small for this to occur for a number of reasons.
The main one is that the development of a living being to be endowed rationally demand a long period of time. On a cosmic scale, this length of time is difficult to occur anywhere with appropriate characteristics (a planet). The conditions that gave rise to the evolution of human beings on Earth are very special, and unless there are other forms of development in other places, it is difficult to the emergence of intelligent life on other planets. The disasters on a cosmic scale changes environments with a frequency greater than the duration required for the development of intelligence.

The most effective method to detect intelligent alien life would be the detection of electromagnetic waves of radio communications. However, these waves travel in space with the speed of light. Since the advent of radio, our waves only reached the maximum distance of 80 light years. This is very little in relation to the size of the Milky Way (about 100,000 light years in diameter). This means that only in 50,000 years we sweep our own galaxy from the advent of intelligent life here capable of emitting radio signals. The same reasoning applies to the alien intelligent life in our galaxy. Probably not detect anything! What we should do is to unite all the nations of the earth to occupy our house in full, the Milky Way. As we get by killing people here, will be difficult this task. We need each one to occupy the whole house.