  Dissipative particle dynamics (DPD) belongs to a class of models and
computational algorithms developed to address mesoscale problems in complex
fluids and soft matter in general. It is based on the notion of particles that
represent coarse-grained portions of the system under study and allow,
therefore, to reach time and length scales that would be otherwise unreachable
from microscopic simulations. The method has been conceptually refined since
its introduction almost twenty five years ago. This perspective surveys the
major conceptual improvements in the original DPD model, along with its
microscopic foundation, and discusses outstanding challenges in the field. We
summarize some recent advances and suggests avenues for future developments.
