  In this paper I review a series of observations which do not agree with the
standard interpretation of the extinction curve. The consequence is that light
we receive from a reddened star must be contaminated by starlight scattered at
very small angular distances from the star. The true extinction curve is a
straight line from the near infrared to the far-UV. If so, all interstellar
grains models must be questionned. Another conclusion concerns the average
properties of interstellar grains which seem much more uniform than previously
thought.
