  We show that Doubly Special Relativity (DSR) can be viewed as a theory with
energy-momentum space being the four dimensional de Sitter space. Different
formulations (bases) of the DSR theory considered so far can be therefore
understood as different coordinate systems on this space. The emerging
geometrical picture makes it possible to understand the universality of the
non-commutative structure of space-time of Doubly Special Relativity. Moreover,
it suggests how to construct the most natural DSR bases and makes it possible
to address the long standing problem of total momentum of many particle systems
from a different perspective.
