Are dogs intelligent?

Today in class we just watched a documental that was produced by The national geographic Channel, which was about the relationship that dogs have had with humans through history and how this relationship has made them one of the most evolved animals.
In this documental a lot of experts in animals behavior explained with diferent exercices how dogs can follow orders from humans not only by hearing but also looking different signs that people do with the eyes or mouth.
For instance, there was this dog called Rico that knew by hard like 20 diferent words and he could recognize them. But not just that, when you added a new object that he didn´t know, he could infer the object because it was the strange one.
Another dog called Sophie that was part of the Police department in USA, had been trained by them due to the most developed sense they have, the smell. It was amazing, this dog could smell swet drops in a 10 km radio, and for him each person has it´s own smell like the digital print.
This documental also tries to explain the bond that has been created between dogs and humans for many years, there was this case, about a Doberman dog called Donnie that her owner picked in a dog shelter when she was four years old. The owner said that in the first months she had to show and teach Donnie many things like go up the stairs, which are the kind of things Donnie couldn´t learn because sha had missed the relationship with an owner (human)in her early years. Then, Donnie began with a weird behavior, she placed her toys creating diferent geometrical figures in the garden specialy triangules. This behavior was analized by an expert who said that probably this was the way Donnie had to express the affection she had with the owner.
In summary this was a very interesting documental that makes us wonder if dogs are intelligent animals or at least one of the most evolved animals after chimps and monkeys. It is impressive to realize how close can a dog and a human bieng can be. When this bond is positive for the dog, it helps the him to reach or to develop his skills in a much better way, but when it´s the opposite, it creates an agressive behavior or deppresive animals.
PD: I liked the idea of the last phrase in the documental, that maybe dogs know us better than we know them.