Nonequilibrium aspects of statistical forces

We review the notion of statistical forces in macroscopic physics. We know them from irreversible thermodynamics as gradients of thermodynamic potentials, but what is their nature and meaning away from equilibrium. We give a statistical mechanical framework leading to non-gradient and non-additive effects for statistical forces, revealing aspects of the thermodynamics and kinetics of driven media. There is a close connection with recent developments in nonequilibrium response theory, giving importance to the notion of dynamical activity.