Seismic and ground-penetrating radar (GPR) methods are widely used in high-resolution geophysical investigations of the shallow subsurface. Technological progress with regard to data acquisition and processing and methodological developments in forward and inverse modelling schemes for interpretation of the seismic and GPR data continuously increase the degree of fine-scale heterogeneity that the methods can resolve. We invite both methodological studies, presentations demonstrating the applicability of the methods, and studies aimed at developing new instrumentation to contribute to this session.