We review two manifestations of chiral symmetry violation involving pions and nucleons, and leading to useful dynamical and structural information on strong interactions. The &pgr;&pgr; scattering amplitude at threshold is fully determined by the chiral symmetry breaking part of the interaction, and, thus, fundamentally constrains the form of the low energy effective lagrangians. We discuss the status and recent developments in the study of the low‐energy &pgr;&pgr; interaction, particularly the new results on reaction &pgr;N→&pgr;&pgr;Nnear threshold, and find that ambiguities persist in the determination of the s‐wave &pgr;&pgr; scattering lengths. The &pgr; Nsigma term is, analogously, determined by chiral symmetry breaking in the &pgr;Nlagrangian. The magnitude of &sgr;&pgr;Nprovides an independent constraint on the QCD structure of the nucleon, insofar as it sets a limit on the nucleon’sss¯content. ©1995 American Institute of Physics.