Assisted suicide is the process by which a person who may otherwise be physically incapable, is provided with the means (drugs or equipment) to commit suicide.
It differs from euthanasia in that, in assisted suicide, the individual performs the critical action that causes the death. In euthanasia, another person does it. 
 Adapted from Wikipedia "Assisted suicide". Online: http://en.wikipedia.org/wiki/Assisted_suicide
Duhaime.Org "Euthanasia in Canada"