  Doubly Special Relativity (DSR) is a class of theories of relativistic motion
with two observer-independent scales. We investigate the velocity of particles
in DSR, defining velocity as the Poisson bracket of position with the
appropriate hamiltonian, taking care of the non-trivial structure of the DSR
phase space. We find the general expression for four-velocity, and we show
further that the three-velocity of massless particles equals 1 for all DSR
theories. The relation between the boost parameter and velocity is also
clarified.
