Systems composed of a few nucleons are subject of experimental studies for many years with the aim to gain precise information on the interaction between nucleons. Intermediate energies, below the threshold for pion production, deserve special attention: it is a region where comparison with exact theoretical calculations is possible, while the sensitivity to various aspects of interaction, like subtle effects of the dynamics beyond the pairwise nucleon-nucleon force, is significant. In addition to differential cross section, the observables related to nuclear polarization are studied, like vector and tensor analyzing powers, spin-correlation coefficients or polarization transfer coefficients. A brief survey of results of recent studies in few-nucleon systems is given.