This Reprint compiles selected peer-reviewed contributions from the Special Issue "Advanced Nanomaterials-Based (Bio-)Sensors for Electrochemical Detection and Analysis", presenting recent advances in nanomaterials applied to chemical and biological sensing platforms. While electrochemical sensing represents a central theme, this Reprint also encompasses complementary sensing strategies, including colorimetric, plasmonic, and gas-sensing approaches, reflecting the multidisciplinary nature of modern sensor research. The collected articles explore the synthesis, functionalization, and integration of advanced nanomaterials such as nanoparticles, two-dimensional materials, polymers, metal oxides, and hybrid heterostructures into sensing interfaces. Emphasis is placed on structure-property-performance relationships, signal transduction mechanisms, and analytical applicability across environmental monitoring, food analysis, biomedical diagnostics, and industrial safety. Overall, this Reprint provides a comprehensive overview of how advanced nanomaterials enable diverse sensing modalities, highlighting converging trends that bridge electrochemical and non-electrochemical detection technologies.