  We discuss the generalization of Doubly Special Relativity to a curved de
Sitter background. The model has three observer-independent scales, the
velocity of light $c$, the radius of curvature of the geometry $\alpha$, and
the Planck energy $\kappa$, and can be realized in a noncommutative position
space. It is possible to construct a model exhibiting a duality for the
interchange of positions and momenta together with the exchange of $\alpha$ and
$\kappa$.
